Friday 29 October 2021

is matter around us Pure 9th cbse mcqs



Question 1.
Which of the following statements are true for pure substances?
(i) Pure substances contain only one kind of particles
(ii) Pure substances may be compound or mixtures
(iii) Pure substances have the same composition throughout
(iv) Pure substances can be exemplified by all elements other than nickel
(a) (i) and (ii)
(b) (i) and (iii)
(c) (iii) and (iv)
(d) (ii) and (iii)

Question 2.
Rusting of an article made up of iron is called
(a) corrosion and it is a physical as well as chemical change
(b) dissolution and it is a physical change
(c) corrosion and it is a chemical change
(d) dissolution and it is a chemical change

Question 3.
A mixture of sulphur and carbon disulphide is
(a) heterogeneous and shows Tyndall effect
(b) homogeneous and shows Tyndall effect
(c) heterogeneous and does not show Tyndall effect
(d) homogeneous and does not show Tyndall effect

Question 4.
Tincture of iodine has antiseptic properties. This solution is made by dissolving
(a) iodine in potassium iodide
(b) iodine in vaseline
(c) iodine in water
(d) iodine in alcoho

Question 5.
Which of the following are homogeneous in nature?
(i) ice
(ii) wood
(iii) soil
(iv) air
(a) (i) and (iii)
(b) (ii) and (iv)
(c) (i) and (iv)
(d) (iii) and (iv)

Question 6.
Blood and sea water are
(a) both mixtures
(b) both are compounds
(c) blood is a mixture whereas sea water is a compound
(d) blood is a compound and sea water is a mixture

Question 7.
Sol and gel are examples of
(a) Solid-solid colloids
(b) Sol is a solid-liquid colloid and gel is liquid solid colloid
(c) Sol is solid-solid colloid and gel is solid-liquid colloid
(d) Sol is a liquid-solid colloid and gel is a solid-liquid colloid

Question 8.
In a water-sugar solution
(a) water is solute and sugar is solvent
(b) water is solvent and sugar is solute
(c) water is solute and water is also solvent
(d) none of these

Question 9.
Boron and carbon are
(a) metalloids
(b) metalloid and non-metal respectively
(c) metal
(d) non-metal and metalloid respectively

Question 10.
Which of the following are physical changes?
(i) Melting of iron metal
(ii) Rusting of iron
(iii) Bending of an iron rod
(iv) Drawing a wire of iron metal
(a) (i), (ii) and (iii)
(b) (i), (ii) and (iv)
(c) (i), (iii) and (iv)
(d) (ii), (iii) and (iv)

Question 11.
Which of the following are chemical changes?
(i) Decaying of wood
(ii) Burning of wood
(iii) Sawing of wood
(iv) Hammering of a nail into a piece of wood
(a) (i) and (ii)
(b) (ii) and (iii)
(c) (iii) and (iv)
(d) (i) and (iv)

Question 12.
Two substances, A and B were made to react to reaction a third substance, A2B according to the following
2 A + B → A2B
Which of the following statements concerning this reaction are incorrect?
(i) The product A2B shows the properties of substances A and B
(ii) The product will always have a fixed composition
(iii) The product so formed cannot be classified as a compound
(iv) The product so formed is an element
(a) (i), (ii) and (iii)
(b) (ii), (iii) and (iv)
(c) (i), (iii) and (iv)
(d) (ii), (iii) and (iv)

Question 13.
Two chemical species X and Y combine together to form a product P which contains both X and Y
X + Y → P
X and Y cannot be broken down into simpler substances by simple chemical reactions. Which of the following concerning the species X, Y and P are correct?
(i) P is a compound
(ii) X and Y are compounds
(iii) X and Y are elements
(iv) P has a fixed composition
(a) (i), (ii) and (iii)
(b) (i), (ii) and (iv)
(c) (ii), (iii) and (iv)
(d) (i), (iii) and (iv)


Question 14.
Which of the following methods would you use to separate cream from milk?
(a) Fractional distillation
(b) Distillation
(c) Centrifugation
(d) Filtration

Question 15.
Cooking of food and digestion of food:
(a) are both physical processes
(b) are both chemical processes
(c) cooking is physical whereas digestion is chemical
(d) cooking is chemical whereas digestion is physical

Question 16.
Mercury and bromine are both
(a) liquid at room temperature
(b) solid at room temperatur
C .metal
D.nonmetals

17. A colloid is a ………….. mixture and its components can be separated by the technique known as …………

18. Ice, water and water vapour look different and display different …………. properties but they are ………… the same.

19.. A mixture of chloroform and water taken in a separating funnel is mixed and left undisturbed for sometime. The upper layer in the separating funnel will be of ………….. and the lower layer will be that of …………..

20. A mixture of two or more miscible liquids, for which the difference in the boiling points is less than 25 K can be separated by the process called ………….

21. When light is passed through water containing a few drops of milk, it shows a bluish tinge. This is due to the …………… of light by milk and the phenomenon is called ………….. This indicates that milk is a …………… solution.

22. What is the name of the metal which exists in liquid state at room temperature?

(a) Sodium

(b) Potassium

(c) Mercury

(d) Bromine

2.3 When the liquid is spun rapidly, the denser particles are forced to the bottom and the lighter particles stay at the top. This principle is used in:

(a) Centrifugation

(b) Fractional distillation

(c) Evaporation

(d) Tunneling

24. What is the name of the metal which exists in liquid state at room temperature?

(a) Mercury

(b) Bromine

(c) Sodium

(d)pottasium

25.Which of the following elements is not a metalloid?

(a)  Boron

(b) Silicon

(c) Germanium

(d) Tungsten

26.  If we put camphor in an open container, its amount keeps on decreasing due to the phenomenon of

(a) Evaporation

(b) Precipitation

(c) Condensation

(d) Sublimation

27. Heterogeneous mixture in which the solute particles do not dissolve and remain suspended throughout the solvent and the solute particles can be seen with the naked eye is known as:

(a) Colloidal solution

(b) Super saturated solution

(c) Sublimation

(d) Suspensions

28.. In tincture of iodine, find the solute and solvent?

(a) alcohol is the solute and iodine is the solvent

(b) iodine is the solute and alcohol is the solvent

(c) any component can be considered as solute or solvent

(d) tincture of iodine is not a solution

29.. The continuous zig-zag movement of colloidal particles in a dispersion medium is called 

(a) Dispersion

(b) Tyndall effect

(c) Brownian movement

(d) Oscillation

30. A pure substance which is made up of only one kind of atom and cannot be broken into two or more simpler substances by physical or chemical means is referred to as

(a) a compound

(b) an element

(c) a molecule

(d) a mixture

31. Which of the following non-metal is a good conductor of electricity
(a) Aluminium

(b) Silicon

(c) Graphite

(d) Gold

32.. Which of the following property does not describe a compound?

(a) It is composed of two or more elements

(b) It is a pure substance.

(c) It cannot be separated into constituents by physical means

(d) It is mixed in any proportion by mass

33. When two liquids do not mix, they form two separate layers and are known as

(a) Miscible liquids

(b) Immiscible liquids

(c) Saturated liquids
(d) Super saturated liquid

34. How one can separate ammonium chloride from a mixture containing ammonium chloride and sodium chloride?

(a) Precipitation

(b) Sublimation

(c) Chromatography

(d) Cetrifugation

35. The amount of solute present per unit volume or per unit mass of the solution/solvent is known as

(a) Composition of solute

(b) Concentration of a solvent

(c) Concentration of a solute

(d) Concentration of a solution

36. According to the definition of pure substance, which of the following is a pure substance?

(a) Ice

(b) Mercury

(c) Iron

(d) All of these

37..  Air shows the property of

 a)  N2

(b)  O2

 (c)  Both (a) and (b)

(d)  None of these.

38. The components of water can be separated by

(a)  Physical methods

(b)  Chemical methods

 c)  Both

(d)  They can�t be separated

39.Mixture can be

a)  homogeneous

(b)  heterogeneous

c)  Both (a) and (b)

(d)  pure substance

40.  Brass is a

 (a)  Compound

(b)  Element

 c)  Homogeneous mixture

(d)  Heterogeneous mixture

41.In sugar solution,

(a)  Sugar is solute, water is solvent

(b)  Sugar is solvent, water is solute

(c)  Both are solutes

(d)  Both are solvents.

42.  Brass is a solution of molten copper in

 (a)  solid zinc

(b)  molten zinc

 (c)  gaseous zinc

(d)  molten tin

43.  24 carat of diamond is equal to
  (a)  200 mg

(b)  200 g

(c)  95% mg

(d)  91% gold

44.  1 carat of diamond i6s equal to

 (a)  200 mg

(b)  200 g

 (c)  100 mg

(d)  100 g

45.  Diamond is lustrous because

(a)  it is colourless

(b)  it is hard

 (c)  it is pure

(d)  its refractive index is high

46..  If we burn graphite,

 (a)  residue will be left

(b)  no residue will be left

  (c)  it will not burn

(d)  it will change into diamond.

47.  Nanometer is an

  (a)  Instrument used for measuring micro-distance

  (b)  Instrument used for measuring macro-distance

 (c)  Unit for measuring micro-distance

 (d)  Unit for measuring macro-distance.

48.Barometer measures

(a)  Pressure

(b)  Atmospheric pressure

(c)  Wind velocity

(d)  Gaseous pressure.

49.Thermometer is an instrument that measures

 (a)  Temperature of substance

(b)  Heat of substance

 (c)  Radiation of substance

(d)  Flow energy in a substance.


50.  Anemometer measures

 (a)  Amount of haemoglobin in blood

(b)  Pollination of plant by the wind

 (c)  Wind resistance

(d)  Wind speed.


5.1 Which of the following is not obtained as a component during the isolation of components by fractional distillation of air?

(a) Carbon dioxide

(b) Argon

(c) Carbon Monoxide
(d) Oxygen

52. For which of the following mixtures, the same method of separation can be followed as a mixture of naphthalene and sand?

(a) Iron fillings and camphor

(b) Iodine in carbon tetrachloride

(c) Sulphur in carbon disulphide

(d) Camphor and ammonium chloride

 

53. Identify the odd one out.

(a) Fog

(b) Mist

(c) Smoke

(d) Cloud

 

5.4. Which of the following is not the common property of smoke and fog?

(a) Physical state of dispersed phase

(b) Physical state of dispersion medium

(c) Smoke is an aerosol.

(d) Smoke is a heterogeneous mixture.

 

55. The elemental gas present in acid rain.

(a) Sulphur dioxide

(b) Carbon monoxide

(c) Nitrogen

(d) Oxygen

 

5.6. Which of the following mixtures has two components and both are compounds ?

(a) Tincture of iodine

(b) Aqueous solution of common salt

(c) Brine Solution

(d) All of these

 

57. Lemonade is prepared by a kid at home. Which component of the lemonade should be a pure substance?

(a) Water

(b) Sugar

(c) Salt

(d) Lemon extract

 

58. Which of the following is the correct representation of a mixture of an element and a compound?



 

59. Identify the statements which comply with bromine dissolved in carbon tetrachloride?

(a) It is a solid-liquid homogeneous mixture.

(b) After separation, bromine cannot be broken down into simpler substances.

(c) Carbon tetrachloride has the properties of carbon and chlorine.

(d) Bromine and carbon tetrachloride can be separated by a separating funnel.

 

60. Which of the following substances undergoes change in state when taken from a cold place (temperature > 273 K) to a place where the average room temperature is 40°?

(a) Sulphur

(b) Water vapour

(c) Mercury

(d) Gallium


61. Which of the following substances, on sufficient cooling, produces a solid which undergoes sublimation under normal conditions?

(a) Water vapour

(b) Ammonia

(c) Carbon dioxide

(d) Chlorine

 

62. The constituents of which substances can be separated only by chemical means?

(a) Brine solution

(b) Alumina

(c) Milk

(d) Gold amalgam

 

63. In a medical shop, I found four bottles labelled as given in the options. Which bottle is considered to be a heterogeneous mixture in which the particles are not visible to the naked eye?

(a) Noxafil oral suspension

(b) Hydrogen peroxide

(c) Aristozyme digestive syrup

(d) Tincture of iodine

 

64. Which liquids used for medical purposes are considered as a sol?

(a) Milk of magnesia

(b) Surgical spirit

(c) Hand sanitiser

(d) Dettol

 

65. A solid can be recovered from a mixture by the method of crystallisation. Which among the following statements comply with the above mixture?

(i) The mixture is homogeneous.

(ii) The mixture taken must be a saturated solution.

(iii) The solid can also be recovered by the method of centrifugation.

(iv) The mixture does not contain any other impurities along with the solid.

 

(a) i, iii and iv

(b) i and ii

(c) ii and iv

(d) Only i

66.) More than one kind of pure form of matter combines forming………..

a) Texture

b) Solution

c) Mixture

d) Component

67.) Dissolved sodium chloride can be separated from water by…………………

a) Chemical process

b) Physical process

c) Chemical process of extraction

d) Physical process of extraction

68.) Non uniform compositions of solutions called………….. solutions.

a) Mixture

b) Texture

c) Homogenous

d) Heterogeneous

69.) Uniform compositions of solutions called………… solutions.

a) Mixture

b) Texture

c) Homogenous

d) Heterogeneous

70.) Homogenous solution may separated by……………….

a) Chemical process

b) Physical process

c) filtration

d) Physical process of evaporation

71) Mixture of two or more metals , or metals and non-metals called as…………

a) Alloy

b) Solution

c) Mixture

d) Metallic mixture

72.) Alloy cannot be separated by……………..method

a) Chemical

b) Evaporation

c) Extraction

d) Physical

73.) Brass is mixture of………….. and……….. .

a) Zinc, carbon

b) Zinc, Mg

c) Zinc, Co

d) Zinc, Copper

74.) Zinc and Copper get mixed by forming……….

a) Steel

b) Brass

c) Gold

d) Zinc carbon mixture

75.) Component present in large amount in solution called………….

a) Solute

b) Sugar

c) Solvent

d) Mixture

76.) The component of solution that dissolved in solvent called……………

a) Solute

b) Sugar

c) Solvent

d) Mixture

77.) A component present in lesser quantity in solution called………..

a) Solute

b) Sugar

c) Solvent

d) Mixture

78.) A component present in more quantity in solution called……………

a) Solute

b) Sugar

c) Solvent

d) Mixture

79) Sugar in water..in that case sugar is …………..

a) Solute

b) Small particles

c) Solvent

d) Mixture

80) Air is ………………….. mixture.

a) Heterogeneous

b) Gas

c) Solid

d) Homogenous

81.) if the solute particle size is smaller than …… then it cannot seen by naked eyes.

a) 1m

b) 1cm

c) 1mm

d) 1nm

82.) When no more solute can be dissolved in solution at given temperature is called………. Solution.

a) Homogenous

b) Heterogeneous

c) Saturated

d) Unsaturated

83.) The amount of the solute present in the saturated solution at this temperature is called its………………….

a) Unsaturation

b) Diffusion

c) Collusion

d) Solubility

84.) If the amount of solute contained in the solution is less than the saturation level…it called as……………

a) Saturated solution

b) Unsaturated solution

c) Homogenous solution

d) Heterogeneous

85.) The concentration of solution is the depend on amount of …………………. Present in given solution.

a) Solvent

b) Solution

c) Pericles

d) Solute

86.) Mass of solute divided by mass of solution multiply by 100 then we get?

a) Solution

b) Mass

c) Mass percentage of solution

d) Volume percentage

87) Mass of solute divided by volume of solution multiply by 100 then we get?

a) Solution

b) Mass

c) Mass percentage of solution

d) Mass by Volume percentage of solutio

88.) If the solution is 400 ml and solvent is 300ml so what is percentage of solute?

a) 30

b) 40

c) 45

d) 25

89.) Solids are disperse in liquids called……

a) Diffusion

b) Dissolution

c) Collusion

d) Suspension

90.) Suspension is ……………… mixture.

a) Saturated

b) Unsaturated

c) Homogenous

d) Heterogeneous

91.) Mixture of water and milk shows……………….. effect.

a) Solubility

b) Diffusion

c) Tyndall

d) Brightening

92) Colloid is ………… mixture.

a) Saturated

b) Unsaturated

c) Homogenous

d) Heterogeneous

93) …………….. particles are scattered a beam of light passing through it and make its path visible.

a) Solute

b) Solvent

c) Colloidal

d) None of the above

94) Foam is the example of…………

a) Scattering light

b) Colloids

c) Saturated solution

d) Unsaturated solutions

95.) We can separate the volatile component from its non volatile solute by the method of………….

a) Extraction

b) Separation

c) Filtration

d) Evaporation

96.) Solid particle are not soluble in solution. That can be separated by the………

a) Extraction

b) Separation

c) Filtration

d) Evaporation

97.) Solid particles are very small in solution which cannot separated by filtration that solution separated by ………………….

a) Dissolution

b) Collusion

c) Suspension

a) centrifugation

98) Centrifugation do not used in………..

a) Diagnostic laboratories

b) Separate butter and cream

c) To separate water and sugar

d) Used in washing machines

99.) Two immiscible layers can separate out in layer depending on their …………………

a) Volume

b) Surface tension

c) Density

d) Viscosity

100.) ……………………….solutions can separated depending upon their densities.

a) Miscible solution

b) Water

c) Immiscible

d) Colloidal

101) Separation of camphor and salt done by…………… method

a) Dissolution

b) Collusion

c) Sublimation

d) Suspension

102.) Separation of dyes and black ink using ……………………. Method.

a) Dissolution

b) Chromatographic

c) Sublimation

d) Suspension

103) ………………. Is a mixture of 2 or more colors.

a) Alloy

b) Dyes

c) Ink

d) Paints

104.) Kroma means?

a) Dyes

b) Colors

c) Paints

d) Natural colors

105) ……………………….. is method to separate two miscible liquids.

a) Collusion

b) Sublimation

c) Suspension

d) Distillation

106.) Chromatographic method used to separate

a) Colors in dye

b) Drug from blood

c) Tea powder from factory

d) Drugs from blood

107) Two miscible liquids having boiling point less than 25K can separated by ……………..

a) Distillation

b) Sublimation

c) Suspension

d) Fractional distillation

108) ………………………… method used for separation of petroleum products.

a) Distillation

b) Sublimation

c) Suspension

d) Fractional distillation

109) Boiling point of oxygen.

a) -280

b) -183

c) -130

d) -220

110.) Boiling point of nitrogen

a) -196

b) -183

c) -130

d) -220

111.) Crystallization method is used to purify………..

a) Liquid

b) Gas

c) Solid

d) Miscible liquids

112.) ………………….. method is used to purify solid.

a) Distillation

b) Sublimation

c) Fractional distillation

a) Crystallization

113) Crystal alum separated from impure samples by……………………. Method.

a) Distillation

b) Sublimation

c) Fractional distillation

d) Crystallization

114.) Chemical change shown in reaction called……………

a) Physical reaction

b) Chemical reaction

c) Saturated

d) Substitution reaction

115.) Two or more atoms combined together forming….

a) Element

b) Molecule

c) Atoms

d) None of the above

116. a pure substance consists of a ………… type of particle/particles
(a) Single
(b) Double
(c) Triple
(d) half

117. Pure substances are ………… by physical methods:
(a) separable
(b) non-separable

118.. Based upon the nature of constituent particle/particles a pure substance is of:
(a) One type
(b) Two types

119. The term element was first used by :
(a) Antoine Laurent Lavoisier
(b) Dalton
(c) Newton
(d) Robert Boyle

120.. An element is a ………. substance.
(a) Good
(b) Pure
(c) Impure
(d) Hard

121.. ……….. is the only metal that is liquid at room temperature.
(a) Bromine
(b) Chlorine
(c) Mercury
(d) Iron

122.‘Boron’ is an example of:
(a) Metal
(b) Non-Metal
(c) Metalloid
(d) Mixture

123.. A mixture in which the constituents are uniformly distributed throughout without any clear boundary of separation is called?
(a) Homogeneous mixture
(b) Non-Homogeneous mixture
(c) Heterogeneous mix

124. in sugar solution sugar is the ………. and water is the ……….
(a) solute, solvent
(b) solvent, solute
(c) solvent, solvent
(d) solute, solute

125.. A solution of iodine in alcohol is known as ……..
(a) tincture of iodine
(b) tincture of sugar
(c) tincture of oxygen
(d) tincture of hydrogen

126. A solution is a ……. mixture?
(a) homogeneous
(b) heterogeneous
(c) both
(d) Saturated

127. The particles of a solution are smaller than:
(a) 1nm
(b) 2nm
(c) 5nm
(d) 0.5nm

128. The amount of solute dissolved in a given volume of the solvent is called :
(a) the concentration of a solution
(b) the concentration of a solvent
(c) the concentration of a solute
(d) none of the above

129. if the amount of solute contained in a solution is less than the saturation level, it is called:
(a) solution
(b) saturated solution
(c) unsaturated solution
(d) suspension

130 . The particles of suspension can be seen with naked eyes:
(a) true
(b) false

131. Physical changes are generally reversible:
(a) true
(b) false

132. ‘burning of coal’ is an example of:
(a) physical change
(b) chemical change
(c) permanent change
(d) temporary  change

Question 133 Air is regarded as a mixture because:
a)Its pressure may very
b)Its temperature may change
c)Its volume changes under different conditions
d)Its composition may vary

Question 134 .Which of the following is a compound?
a)Stainless steel
b)Bronze
c)Graphite
d)Hydrogen sulphide

Question 135.The process used to separate oil and water is:
a)Distillation
b)Sublimation
c)Separating funel
d)chromatography

Question 136n which of the following the constituents are present in any ratio?
a)Mixture
b)Compound
c)Solution
d)Colloid

Question 137.A mixture of common salt, sulphur, sand and iron filings is shaken with carbon disulphide and filtered through a filter paper. The filtrate is evaporated to dryness in a china dish. What will be left in the dish after evaporation?
a)Sand
b)Sulphur
c)Iron filings
d)Common salt

Question 138. Two substances A and B when bought together form a substance C with the evolution of heat. The properties of C are entirely different from those of A and B. the substance C is:
a)A compound
b)An element
c)A mixture
d)None of the above

Question 139Camphor can be purified by:
a)Distillation
b)Filtration
c)Sedimentation
d)Sublimation

Question 140.Which one of the following will result in the formation of a mixture?
a)Crushing of a marble tile into small particles
b)Breaking of ice cubes into small pieces
c)Adding sodium metal to water
d)Adding milk in water

Question 141.Purity of a solid substance can be checked by its:
a)Boiling point
b)Melting point
c)Solubility in water
d)Solubility in alcohol

Question 142.A mixture of ethanol and water ca be separated by:
a)Filtration
b)Decantation
c)Fractional distillation
d)Sublimation

Question 133..Salt can be obtained from sea water by:
a)Filtration
b)Decantation
c)Evaporation
d)Sublimation

Question 144.A sample contains two substances and has uniform properties. The sample is:
a)A compound
b)A heterogeneous mixture
c)An element
d)A homogeeous mixture

Question 145.A mixture of ZnCl2 and PbCl2 can be separated by:
a)Distillation
b)Crystallization
c)Sublimation
d)Adding acetic acid

Question 146..A mixture of methyl alcohol and acetoe can be separated by:
a)Distillation
b)Fractional distillation
c)Steam distillation
d)Distillation under reduced pressure

Question 147.Mixture of sand and sulphur may best be separated by:
a)Fractional crystallization from aqueous solution
b)Magnetic method
c)Fractional distillation
d)Dissolving in CS2 and filtering

Question 148.Which component of the mixture ( Fe + S ) reacts with dil. HCI and gives hydrogen gas?
a)Sulphur
b)Iron
c)Both
d)None

Question 149..Which of the following is considered to be a pure substance?
a)Granite
b)Sodium chloride
c)Muddy water
d)Milk of magnesia

Question 150.Physical properties of a mixture:
a)Vary with the amount of substance
b)Depend on the volume of the substance
c)Depend on the organization of the substance
d)Vary depending upon its components

Question 151.Compounds:
a)Are the same as mixtures?
b)Can be separated by their physical properties
c)Contain only type of element
d)Are different kinds of atoms chemically combined with each other?

Question 152.White gold is used in jewelry and contains two elements, gold and palladium. A jeweler has two different samples that are both identical in appearance and have a uniform composition throughout. What can be said about the samples?
a)They are homogeneous mixtures and be classified as metallic alloys.
b)The materials are heterogeneous mixtures and can be classified by their components.
c)The samples have variable compositions and are classified as metallic solutions.
d)The samples are heterogeneous mixtures that can be separated using magnetic properties.


Question 153.To prepare iron sulphide, by heating a mixture of iron filings and sulphur powder, we should use a:
a)Copper dish
b)Watch glass
c)China dish
d)Petri dish

Question 154.Which of the following is an example of a heterogeneous substance?
a)Bottled water
b)Table salt
c)Pieces of copper
d)Candle

Question 155.Which of the following is an example of a homogeneous substance?
a)Granite
b)Copper sulphate
c)M& M candy
d)Muddy water

Question 156.Which flow chart correctly describes a homogeneous material?
a)Unknown - density - 3 layers
b)Unknown – filtration – two substances
c)Unknown – magnet – two substances
d)Unknown – boiling – one temperature

Question 157.A student is given a mixture of iron filings and sulphur in thee ratio 1 : 2 by weight. He was then asked to heat the mixture over a flame and to observe the olor change. The student will observe that the mixture becomes:
a)Black
b)Grey
c)Yellow
d)Orange

Question 158.Filtration can be used to separate:
a)Solids from solids
b)Liquids from solids
c)Liquids from liquids
d)Liquids from gases

Question 159..One common method used to separate dyes is:
a)Filtration
b)Distillation
c)Chromatography
d)Conductivity

Question 160.Melting points can separate materials because:
a)Substances melt at different temperatures
b)Molecules vibrate rapidly when heated
c)Heat causes molecules to disintegrate
d)May substances fuse at the melting point

Question 161.Distillation is a good separation technique for:
a)Solids
b)Liquids
c)Solid alloys
d)Gases

Question 162.Solubility is a good separation technique for:
a)Pure metals
b)Noble gases
c)Different salts
d)Metallic alloys

Question 163.Magnetism is most beneficial for separating:
a)Gases and non- metallic liquids
b)Magnetic solids and solids such as sulfur
c)Non- metallic solids and solids such as sulfur
d)Non- magnetic solids from non- magnetic liquids

Question 164..Before the heating when iron filing mixed with sulphur. Is this reaction will show chemical change:
a)Yes
b)No
c)Initially physical then chemical change
d)Initially chemical then physical change

. 165What is the name of the metal which exists in liquid state at room temperature?
(a) Sodium
(b) Potassium
(c) Mercury
(d) Bromine

166. When the liquid is spun rapidly, the denser particles are forced to the bottom and the lighter particles stay at the top. This principle is used in:
(a) Centrifugation
(b) Fractional distillation
(c) Evaporation
(d) Tunneling

167. What is the name of the metal which exists in liquid state at room temperature?
(a) Mercury
(b) Bromine
(c) Sodium
(d) Potassium

168 Which of the following elements is not a metalloid?
(a)  Boron
(b) Silicon
(c) Germanium
(d) Tungsten

169.  If we put camphor in an open container, its amount keeps on decreasing due to the phenomenon of
(a) Evaporation
(b) Precipitation
(c) Condensation
(d) Sublimation

170 Heterogeneous mixture in which the solute particles do not dissolve and remain suspended throughout the solvent and the solute particles can be seen with the naked eye is known as:
(a) Colloidal solution
(b) Super saturated solution
(c) Sublimation
(d) Suspensions

171. In tincture of iodine, find the solute and solvent?
(a) alcohol is the solute and iodine is the solvent
(b) iodine is the solute and alcohol is the solvent
(c) any component can be considered as solute or solvent
(d) tincture of iodine is not a solution

172. The continuous zig-zag movement of colloidal particles in a dispersion medium is called
(a) Dispersion
(b) Tyndall effect
(c) Brownian movement
(d) Oscillation


173. A pure substance which is made up of only one kind of atom and cannot be broken into two or more simpler substances by physical or chemical means is referred to as
(a) a compound
(b) an element
(c) a molecule
(d) a mixtur

174. Which of the following non-metal is a good conductor of electricity?
(a) Aluminium
(b) Silicon
(c) Graphite
(d) Gold

175.. Which of the following property does not describe a compound?
(a) It is composed of two or more elements
(b) It is a pure substance.
(c) It cannot be separated into constituents by physical means
(d) It is mixed in any proportion by mass

176.. When two liquids do not mix, they form two separate layers and are known as
(a) Miscible liquids
(b) Immiscible liquids
(c) Saturated liquids
(d) Super saturated liquids

177. How one can separate ammonium chloride from a mixture containing ammonium chloride and sodium chloride?
(a) Precipitation
(b) Sublimation
(c) Chromatography
(d) Cetrifugation

178. The amount of solute present per unit volume or per unit mass of the solution/solvent is known as
(a) Composition of solute
(b) Concentration of a solvent
(c) Concentration of a solute
(d) Concentration of a solution

179. According to the definition of pure substance, which of the following is a pure substance?
(a) Ice
(b) Mercury
(c) Iron
(d) All of these

180. In the chemical classification, matter is classified into
a. solids, liquids and gases. b. pure substances and mixtures.
c. elements and compounds. d. metals, non-metals and metalloids.

181.Which of the following is not a characteristic of pure substances?
a. Pure substances are made up of only one type of particles.
b. Pure substances have variable compositions.
c. Pure substances are perfectly homogeneous.
d. Pure substances have definite melting and boiling points.

182.. A/An is the simplest form of matter that cannot be broken down further into simpler
substances by chemical methods.
a. mixture b. compound
c. element d. alloy

183.. Name the metal which exists as a liquid at room temperature.
a. Sodium b. Aluminium
c. Thallium d. Mercury

184.is the only non-metal which exists as a liquid at room temperature.
a. Carbon b. Hydrogen
c. Bromine d. Iodine

185. A substance which is made up of two or more elements chemically combined together in a definite proportion
by mass is known as a/an
a. alloy. b. compound.
c. homogeneous mixture. d. heterogeneous mixture.

186. What is the ratio of hydrogen and oxygen by mass in H2O2?
a. 1 : 8 b. 8 : 1
c. 1 : 16 d. 16 : 1

187. Which of the following is not a homogeneous mixture?
a. Mixture of sodium chloride and water b. Mixture of sugar and water
c. Mixture of glucose and water d. Mixture of clay and water

188. Which of the following is a heterogeneous mixture?
a. Mixture of acetic acid and water b. Mixture of ethanol and water
c. Mixture of acetone and water d. Mixture of kerosene oil and water

189. Which of the following statements is false?
a. Pure substances are further classified as elements and compounds.
b. The components of a mixture do not retain their individual properties.
c. A compound has a definite chemical composition.
d. A mixture has a variable chemical composition.

190. The particles of a solution are less than in diameter.
a. 1 nm b. 0.1 nm c. 0.5 nm d. 0.05 nm

191. Bronze is an alloy of
a. copper and zinc. b. copper and tin.
c. iron and aluminium. d. iron and chromium.

192.. A solution is prepared by dissolving 10 g of sodium chloride in 40 g of water. What is the mass by mass percentage
of this solution?
a. 25 % b. 20 %
c. 50 % d. 80 %

193 A 15 % (m/m) aqueous solution of glucose is prepared by dissolving 13.5 g of glucose in x g of water. Calculate
the value of x.
a. 103.5 g b. 100 g
c. 90 g d. 76.5 g

194.. The volume of a 20 % (v/v) aqueous solution of ethanol is 80 mL. Calculate the volume of ethanol present in this
solution.
a. 40 mL b. 20 mL
c. 16 mL d. 4 mL

195. A solution which contains more quantity of the solute that it can dissolve at a particular temperature is called
a/an solution.
a. dilute b. unsaturated
c. saturated d. supersaturated

196. Which of the following is a suspension?
a. Vinegar b. Milk
c. Mixture of clay and water d. Sodium amalgam

197.Which of the following substances will not show Tyndall effect?
a. Milk b. Ink
c. Brine d. Fog

198. Shaving cream is a/an
a. aerosol. b. emulsion.
c. sol. d. foam.

199.Identify the correct statement from the following.
a. A solution does not scatter light.
b. A colloid is a homogeneous mixture.
c. The particles of a suspension cannot scatter light.
d. The particles of a colloid are larger than the particles of a suspension.

200. is an emulsion.
a. Butter b. Milk of magnesia
c. Foam d. Milk

201. In a/an , both the dispersed phase and the dispersion medium are in liquid state.
a. aerosol b. foam
c. emulsion d. gel

202. A mixture of can be separated by magnetic separation.
a. naphthalene and common salt b. sulphur and common salt
c. iodine and sulphur d. iron filings and sulphur

203. What is the random zig-zag motion of colloidal particles called?
a. Tyndall effect b. Rayleigh’s scattering
c. Brownian movement d. Adsorption

204 The components of a mixture of ammonium chloride and sodium chloride can be separated by
a. filtration. b. sublimation.
c. evaporation. d. crystallisation.

205. In which of the following substances, both the dispersed phase and the dispersion medium are in solid state?
a. Face cream b. Milky glass
c. Jelly d. Pumice

206. Name the process which is used for separating the different components of air.
a. Chromatography b. Simple distillation
c. Fractional distillation d. Centrifugation

207.. Salt obtained from seawater is purified by
a. evaporation. b. crystallisation.
c. distillation. d. centrifugation.

208.Which of the following is the principle of separating a mixture of two immiscible liquids by using a separating
funnel?
a. Denser particles of a mixture are forced to the bottom while lighter particles stay at the top when the
mixture is spun rapidly.
b. Immiscible liquids separate out in layers depending on their densities.
c. Different liquids boil at different temperatures.
d. A substance has different solubilities in different solvents.

209.. The components of ink can be separated by
a. simple distillation. b. centrifugation.
c. crystallisation. d. chromatography


210. Which of the following statements is/are correct?
(a) All the constituent particles of a pure substance
are the same in their chemical nature.
(b) A pure substance consists of a single type of
particles.
(c) Most of the matter around us exist as mixtures of
two or more pure components.
(d) All of these

211. If the components of the substance can be separated
by a chemical change only then it is a/an
(a) element (b) compound
(c) mixture (d) none of these
Ans : (b) compound

212. Identify the correct statement(s).
(a) Mixtures which have a uniform composition
throughout are called homogeneous mixtures or
solutions.
(b) A homogeneous mixture can have a variable
composition.
(c) Heterogeneous mixtures have non-uniform
compositions.
(d) All of these
Ans : (d) All of these

213 . What type of mixtures are separated by crystallisation?
(a) A mixture in which one component is soluble in a
solvent.
(b) A mixture in which impurities are soluble in a
solvent.
(c) A mixture in which both the components are
soluble in a solvent.
(d) A mixture in which both the components are
insoluble in water.
Ans : (a) A mixture in which one component is soluble

214. The zigzag movement of dispersed phase particle in a
colloidal system is known as
(a) Brownian motion
(b) translational motion
(c) circular motion
(d) linear motion
Ans : (a) Brownian motion

The zigzag motion of colloidal particles is called
Brownian motion.

215 . A student mixed a small amount of iron filings and
sulphur powder in a dish. He could not affect the
separation by simple hand-picking. Which liquid will
you suggest to affect the separation?
(a) Carbon disulphide (b) Cold water
(c) Boiling water (d) Kerosene
Ans : (a) Carbon disulphide
Sulphur is soluble in carbon disulphide while iron
filings remain insoluble. Hence, the sulphur will

216. The fine particles of an insoluble substance uniformly
dispersed throughout a gas or liquid is called
(a) suspension (b) precipitate
(c) colloidal solution (d) impurity
Ans : (c) colloidal solution
In colloidal solution, dispersed phase is dispersed
uniformly in

217. Substance P has the following properties:
1. Melts at cC80
2. Boils at 150cC
3. Insoluble in water
Which method of separation would you use to obtain
pure P from a mixture of P and water?
(a) Paper chromatography
(b) Fractional distillation
(c) Crystallisation
(d) Filtration
Ans : (d) Filtration
As substance P is insoluble in water, it can be
separated by filtration.
218

218. What kind of solution is gel?
(a) Colloid (b) Mixture
(c) Emulsion (d) Suspension
Ans : (a) Colloid
Gel is a colloid in which liquid phase is dispersed in
solid dispersion medium e.g. jelly, cheese, butter, etc.
219 Pigments of natural colours can be separated by
(a) chromatography (b) centrifugation
(c) filtration (d) sublimation
Ans : (a) chromatography
By chromatography technique, components of natural
colours can be separated.

220 In ‘tincture of iodine’, a solute is .......... and a solvent
is .......... .
(a) alcohol, iodine (b) iodine, tin
(c) iodine, alcohol (d) tin, iodine
Ans : (c) iodine, alcohol
A solution of iodine in alcohol is known as ‘tincture of
iodine’. It has iodine (solid) as the solute and alcohol
(liquid) as the solvent.
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1
221. Which of the following statements are correct about
properties of colloids?
1. A colloid is a homogeneous mixture.
2. The size of particles of a colloid is too small to be
individually seen by naked eye.
3. Colloids are big enough to scatter a beam of light
passing through it and make its path visible.
(a) 1, 2 and 3 (b) 2 and 3
(c) 1 and 2 (d) 1 and 3
Ans : (b) 2 and 3
Colloidal solutions are heterogeneous in nature.

222. When a beam of light is passed through a colloidal
solution, it gets
(a) reflected (b) absorbed
(c) scattered (d) refracted
Ans : (c) scattered
The scattering of beam of light on passing through
colloidal solution is known as Tyndall effect.

223. Iodized common salt is
(a) homogeneous mixture
(b) heterogeneous mixture
(c) pure substance
(d) oxidized substance
Ans : (a) homogeneous mixture
Iodized common salt is a homogeneous mixture since
the composition of iodine and salt is fixed throughout
the iodized salt and there are no visible boundaries.
224. Pigments of natural colours can be separated by
(a) chromatography (b) centrifugation
(c) filtration (d) sublimation

225. The fine particles of an insoluble substance uniformly
dispersed throughout a gas or liquid is called
(a) suspension (b) precipitate
(c) colloidal solution (d) impurity
Ans : (c) colloidal solution
In colloidal solution dispersed phase is dispersed
uniformly in dispersion medium.
226. Which of the following upon shaking with water will
not form a true solution?
(a) Alum (b) Common salt
(c) Albumin (d) Sucrose
Ans : (c) Albumin
Albumin will form a colloidal solution since it is not
soluble in water.
227. Which of the following will show Tyndall effect?
(a) Starch solution
(b) Sodium chloride solution
(c) Copper sulphate solution
(d) Sugar solution
Ans : (a) Starch solution
Starch solution will show Tyndall effect i.e. scattering
of light since it is a colloidal solution.
228. An emulsion is a colloidal solution formed by mixing
(a) two miscible liquids
(b) any two liquids
(c) any two gases
(d) two immiscible liquids
Ans : (d) two immiscible liquids
Emulsion is a colloidal solution of two immiscible
liquids mixed together e.g., milk.
229 The size of colloidal solution is in the range of
(a) 1-100 nm (b) 100-1000 nm
(c) 10 m m 10 5 7 - - - (d) 10 10 m 7 9 -
Ans : (a) 1-100 nm
The size of colloidal particles is in the range of 1 to
100 nm.

230. Brass contains
(a) gold and copper (b) copper and zinc
(c) zinc and silver (d) copper and silver
Ans : (b) copper and zinc
Brass is an alloy of copper and zinc.

231. Which of the following is a homogeneous mixture?
(a) Solution of sugar in water
(b) Chalk powder in water
(c) Kerosene oil in water
(d) None of these
Ans : (a) Solution of sugar in water
Sugar solution is a homogeneous mixture.

232. Solutions with low concentrations of solutes are
(a) concentrated solutions (b) dilute solutions
(c) solvents (d) none of th
Solutions which contain small amount of solute are
known as dilute solutions.

233.Which of the following statement is correct?
(a) A pure substance must contain only one type of
atom.
(b) A mixture containing two compounds must be
heterogeneous.
(c) A heterogeneous mixture must contain atleast
three elements.
(d) A homogeneous mixture must be uniform.
Ans : (d) A homogeneous mixture must be uniform.
The mixture which has a uniform composition
throughout, is known as homogeneous mixture.

234. If we heat iodine, then it is a
(a) physical change (b) chemical change
(c) no change (d) colour change
Ans : (a) physical change
Iodine is converted into iodine vapours which can be
condensed back to get iodine (solid).

235 Which of the following is not an example of a physical
change?
(a) Dissolving sugar in water
(b) Casting iron in moulds
(c) Setting of cement
(d) Magnetisation of iron
Ans : (c) Setting of cement
Setting of cement is an example of permanent change
which is irreversible, thence is not a physical change.

236. Smoke is an example of
(a) gas dispersed in liquid
(b) gas dispersed in solid
(c) solid dispersed in gas
(b) solid dispersed in solid
Ans : (c) solid dispersed in gas
In case of smoke solid particles are dispersed in gas.

237.. Separation of petroleum into its components is done
by
(a) chromatography (b) sublimation
(c) distillation (d) fractional distillation
Ans : (d) fractional distillation
Fractional distillation us used to separate components
of petroleum

238. Which one of the following is correctly matched?
(a) Emulsion - curd (b) Foam - mist
(c) Aerosol - smoke (d) Solid sol - cake
Ans : (c) Aerosol - smoke
Smoke is aerosol, solid dispersed in gas

239. Iron rod turns red on heating. The change is a
(a) physical change
(b) permanent change
(c) physical and chemical change
(d) chemical change
Ans : (a) physical change

240.. A mixture contains four solid compounds A, B, C,
D. On heating C changes to vapour state. C can be
separated from rest of the solids by
(a) crystallisation (b) sublimation
(c) distillation (d) filtration
Ans : (b) sublimation
Sublimation

241.. Chemical changes are
(a) temporary, reversible and a new substance is
produced
(b) always accompanied by exchange of light
(c) permanent, irreversible and a new substance is
produced
(d) never accompanied by exchange of light and heat
energy
Ans : (c) permanent, irreversible and a new substance
is produced

242. Identify the false statement.
(a) Colloids are homogeneous
(b) Colloids show Tyndall effect
(c) Colloids show Brownian movement
(d) The size of colloidal particles ranges between
1-100 nm.
Ans : (a) Colloids are homogeneous
Colloids are heterogeneous in nature, made up of two
different phases viz. dispersed phase and dispersion
medium.

243.. Select the incorrect statements(s).
1. Although ice, water and water vapour all look
different and display different physical properties,
they are chemically the same.
2. During burning of a candle, both physical and
chemical changes take place.
3. Both water and cooking oil are liquid but their
chemical characteristics are different. They differ
in odour and inflammability.
4. It is the physical property of oil that makes it
different from water.
(a) 1 and 2 (b) 2 and 3
(c) 1, 2 and 3 (d) Only 4
Ans : (d) Only 4
It is the chemical property of oil that makes it different
from water.

244.. Which gas present in air has the highest boiling point?
(a) Oxygen (b) Nitrogen
(c) Argon (d) Hydrogen
Ans : (a) Oxygen

245. Which of the following are metalloid?
1. Boron
2. Sodium
3. Silicon
4. Chlorine
5. Germanium
(a) 2 and 4 (b) 1 and 4
(c) 3 and 5 (d) 1, 3 and 5
Ans : (d) 1, 3 and 5
Sodium is a metal while chlorine is a non-met
al.

246. If the component of the substance can be separated by
a chemical change only then it is
(a) element (b) compound
(c) mixture (d) both (a) and (b)
Ans : (b) compound
A compound can be separated into its components by
chemical means while an element cannot be further
separated. A mixture can be separated by physical
means.

247.. Select the old one out.
(a) Carbon (b) Oxygen
(c) Iodine (d) Mercury
Ans : (d) Mercury

248. An example of a chemical change is
(a) formation of clouds
(b) glowing of an electric light
(c) dropping sodium into water
(d) dissolving of salt in water
Ans : (c) dropping sodium into water
Formation of clouds, glowing of an electric light
and dissolving of salt in water are the examples of a
physical change.

249.. Which of the following is not true for a compound?
(a) A compound is heterogeneous in nature
(b) A compound contains different elements in a fixed
ratio.
(c) Properties of a compound are entirely different
form those of the elements present in it.
(d) Constituents of a compound cannot be separated
by simple physical methods.
Ans : (a) A compound is heterogeneous in nature

250.. Which of the following involves both physical and
chemical change?
(a) Burning of a candle (b) Rusting of iron
(c) Cooking of food (d) Boiling of water
Ans : (a) Burning of a candle

251.. What is the name of the insoluble substance which
settles to the bottom of its container?
(a) Solute (b) Solvent
(c) Sediment (d) Slag
Ans : (c) Sediment
Sediment is the insoluble part of a mixture which
settles down at the bottom of its container
.
252. We can separate a pure solid from its solution by
(a) crystallization (b) simple distillation
(c) sedimentation (d) both (a) and (b)
Ans : (a) crystallization
Only pure solid will be crystallised from its saturated
solution.

253.. Soda water is a solution of carbon-dioxide in water.
What is this solution composed of?
(a) Liquid solute in a gaseous solvent
(b) Gaseous solute in a liquid solvent
(c) Liquid solute in a liquid solvent
(d) Gas in suspended form in liqui

254.. The smell of perfume gradually spreads across a room
due to .........

255. As the volume of a specific amount of gas decreases,
it’s pressure ..........

256.. Rapid evaporation depends on the .......... area exposed
to atmosphere.

257. As the temperature of a system increases, the pressure
of the gases ..........

258. Matter is made up of small ..........

259.. Liquids that move quickly downhill are described as
having .........

260.. The forces of attraction between the particles are in
solids, ......... in liquids and .......... in gases.

261.Forces of attraction in liquids are .......... than in solids.

262........... is the change of gaseous state directly to solid
state without going through liquid state, and vice-
versa.

263.. The pressure inside a sealed tube, if you raise the
temperature go .........

264. Evaporation causes ........

265. Usually the total charge of a plasma is .........

266. Latent heat of fusion is the amount of heat energy
required to change 1 kg of solid into liquid at its ..........

267.Gas molecules at higher temperatures have more
.......... than at cooler temperatures have more ..........
than at cooler temperatures.

268.. Solid, liquid and gas are called the three .......... of
matter

269. As the temperature of a gas decreases, its volume ......

270. Boiling is a bulk phenomenon.

271. Plasmas are all made of the same ions. They have
different colours due to different amounts of electricity.

272. Evaporation is a surface phenomenon.

273.A system that changes from a solid state to a liquid
state gains energy.

274.. The rate of evaporation depends only on the surface
area exposed to the atmosphere.

275. You may find plasma in a star.

276.Latent heat of vaporisation is the heat energy required
to change 1 kg of a liquid to gas at atmospheric
pressure at its melting point.

277. If we pour liquid nitrogen ( ) N2 into a glass, it will
change its state to a solid.

278.. Water at room temperature is a liquid.

279. Evaporation and boiling are the same processes
because molecules move from a liquid to gaseous state.

280.. Atoms in a liquid are farther apart than the atoms in
a gas.

281.It is just as easy to compress a liquid, as it is to
compress a gas.

282. The molecules in a gas are in constant motion.

283. Because electrons have been stripped away from atoms
in plasma, plasmas have a negative charge.

284.. Gases present in air have the same pressure throughout
the entire atmosphere.

285.All materials move from solid to liquid to gas as the
temperature increases.
.
286.. Assertion : When a beam of light is passed through
a colloidal solution placed in a dark place the path of
the beam becomes visible.
Reason : Light gets scattered by the colloidal particles.
Ans : (a) Both assertion (A) and reason (R) are true
and reason (R) is the correct explanation of
assertion (A).
Light is scattered by colloidal particles, making the
path of the beam visible.

287. Assertion : A mixture of benzoic acid and naphthalene
can be separated by crystallization from water.
Reason : Benzoic acid is soluble in hot water but
naphthalene is insoluble in hot water.
Ans : (a) Both assertion (A) and reason (R) are true
and reason (R) is the correct explanation of
assertion (A).
Benzoic acid is soluble in hot water but naphthalene
is not soluble, hence separation can be carried ou
hot water crystallisation.

288. Assertion : A solution of table salt in a glass of water
is homogeneous.
Reason : A solution having different composition
throughout is homogeneous.
Ans : (c) Assertion (A) is true but reason (R) is false.
A solution having same composition throughout is
homogeneous.

289. Assertion : A mixture of sugar and benzoic acid can
be separated by shaking with ether.
Reason : Sugar is insoluble in water.
Ans : (c) Assertion (A) is true but reason (R) is false.
Sugar is soluble in water and insoluble in ether.

290. Assertion : In sublimation, a substance changes
directly from solid to vapour without passing through
liquid state and vice-versa.
Reason : Distillation involves two processes i.e.,
vaporisation and condensation.
Ans : (b) Both assertion (A) and reason (R) are true
but reason (R) is not the correct explanation of
assertion (A).
Both are definitions of

291.. Assertion : True solution exhibits Tyndall effect.
Reason : Particles are very large in size.
Ans : (d) Assertion (A) is false but reason (R) is true.
True solutions do not exhibit Tyndall effect since the
particle size is very small to scatter light.

292.. Assertion : Colloidal solutions are stable and the
colloidal particles do not settle down.
Reason : Brownian movement counters the force of
gravity acting on colloidal particles.
Ans : (a) Both assertion (A) and reason (R) are true
and reason (R) is the correct explanation of
assertion (A).
Due to constant movement of particles colloidal
particles do not settle down.

293.. Assertion : A solution of table salt in a glass of water
is homogeneous.
Reason : A solution having different composition
throughout is homogeneous.
Ans : (c) Assertion (A) is true but reason (R) is false.
A solution having same composition throughout is
homogeneous.

294. Assertion : Impure benzoic acid can be purified by
sublimation.
Reason : Benzoic acid sublimes on heating.
Ans : (a) Both assertion (A) and reason (R) are true
and reason (R) is the correct explanation of
assertion (A).
Benzoic acid sublimes on heating while impurities do
not.

295.Assertion : Tyndall effect is an optical property.
Reason : Electrophoresis is an electrical property.
Ans : (b) Both assertion (A) and reason (R) are true
but reason (R) is not the correct explanation of
assertion (A).
Scattering of light by colloidal particles is an optical
activity. Coagulation of colloidal particles under an
electrical field is an electrical property

296.. Assertion : A mixture of acetone and methanol can be
separated by fractional distillation.
Reason : The difference between their boiling points
is very less.
Ans : (a) Both assertion (A) and reason (R) are true
and reason (R) is the correct explanation of
assertion (A).
Whenever the difference in boiling points of two liquids
is less than cC25 they are separated by fractional
distillation.

297.Assertion : Chloroform and benzene form a pair of
miscible liquids and they are separated by fractional
distillation.
Reason : Boiling point of benzene is less than that of
chloroform.
Ans : (c) Assertion (A) is true but reason (R) is false.
Chloroform (b.pt. cC60 ) and benzene (b.pt. 80c) can
be separated by fractional distillation since fractional
distillation is used for the separation of two or more
liquids with difference in their boiling points of less
than cC25 .

298. Assertion : A mixture of camphor and ammonium
chloride cannot be separated by sublimation.
Reason : Camphor on heating sublimes, ammonium
chloride does not.
Ans : (c) Assertion (A) is true but reason (R) is false.
Both camphor and ammonium chloride sublime on
heating.

299.Assertion : A mixture of glucose and m-dinitrobenzene
can be separated by shaking it with ether.
Reason : Glucose is soluble in water.
Ans : (b) Both assertion (A) and reason (R) are true
but reason (R) is not the correct explanation of
assertion (A).

300.⁰lAssertion : Hot water is used for separation of benzoic
acid from naphthalene.
Reason : Whenever a crystal is formed it tends to  leave out the impurities.
Ans : (b) Both assertion (A) and reason (R) are true
but reason (R) is not the correct explanation of
assertion (A).
Benzoic acid dissolves in hot water but naphthalene
does not therefore, hot water is used for separation of
benzoic acid from napthalene

301 Assertion : When a beam of light is passed through a colloidal solution placed in a dark place the path of the beam becomes visible.
Reason : Light gets scattered by the colloidal particles.

Answer

302.Assertion : A mixture of benzoic acid and naphthalene can be separated by crystallization from water.
Reason : Benzoic acid is soluble in hot water but naphthalene is insoluble in hot water.

Answer

303.Assertion : A solution of table salt in a glass of water is homogeneous.
Reason : A solution having different composition throughout is homogeneous.

Answer

304.Assertion : A mixture of sugar and benzoic acid can be separated by shaking with ether.
Reason : Sugar is insoluble in water.

Answer

305.. Assertion : In sublimation, a substance changes directly from solid to vapour without passing through
liquid state and vice-versa.
Reason : Distillation involves two processes i.e., vaporisation and condensation.

Answer

306.Assertion : True solution exhibits Tyndall effect.
Reason : Particles are very large in size.

Answer

307.. Assertion : Colloidal solutions are stable and the colloidal particles do not settle down.
Reason : Brownian movement counters the force of gravity acting on colloidal particles.

Answer

308  Assertion : A solution of table salt in a glass of water is homogeneous.
Reason : A solution having different composition throughout is homogeneous.

Answer

309.. Assertion : Impure benzoic acid can be purified by sublimation.
Reason : Benzoic acid sublimes on heating.

Answer

310.. Assertion : Tyndall effect is an optical property.
Reason : Electrophoresis is an electrical property.

Answer

311. Assertion : A mixture of acetone and methanol can be separated by fractional distillation.
Reason : The difference between their boiling points is very less.

Answer

312 Assertion : Chloroform and benzene form a pair of miscible liquids and they are separated by fractional
distillation.
Reason : Boiling point of benzene is less than that of chloroform.

Answer

313. Assertion : A mixture of camphor and ammonium chloride cannot be separated by sublimation.
Reason : Camphor on heating sublimes, ammonium chloride does not.

Answer

314. Assertion : A mixture of glucose and m-dinitrobenzene can be separated by shaking it with ether.
Reason : Glucose is soluble in water.

Answer

Q.315. Assertion : Hot water is used for separation of benzoic acid from naphthalene.
Reason : Whenever a crystal is formed it tends to leave out impurities

316. Assertion: Oxygen is an element. Reason: It cannot be decomposed by a physical or a chemical process.

317. Which of the following is/are true about hetrogenous mixtures?

a. An opaque suspension is a hetrogenous mixture. b. Collodial solutions are hetrogenous mixtures. c. A mixture of two miscible liquids is a hetrogenous mixture.

. 318Which of the following is a true statement for a pure substance or a compound?

a. The elements in a compound are present in a definite proportion by weight. b. It can be broken down into a simpler type of matter (elements) by chemical means but not by physical means. c. Properties of a compound are an average of the properties of its constituents.

319 Which of the following pairs of colloids and their dispersed phase is correct?

• Smoke - gas

• Shaving cream - liquid

• Milk of magnesia - liquid

• Cheese - liquid

• Sponge - solid

320.Which of the following shows Tyndall effect?

a. Soda water b. Milk c. Muddy water

• Only a

• Only b

• Only c

• Only a and c

• All of these

321. Which of the following is false about a Solution?

• It is a heterogeneous mixture.

• The particles of a solution are very small and invisible to the naked eye.

• The path of light is not visible in a solution.

• The constituents of a solution cannot be separated by sedimentation.

• The constituents of a solution cannot be separated by filtration.

322. Which of the following statements is/are correct?

a. The concentration of a solution is the amount of solute present per unit volume or per unit mass of the solution/solvent. b. The particles of a suspension are called the dispersed phase. c. On heating of two elements in a mixture strongly we get a compound, which has totally different properties as compared to the combining elements.

• Only a

• Only b

• Only c

• Only a and c

• All of these

323. Which of the following processes is used for the separation of insoluble solid particles from a solid-liquid mixture, if the solid particles are very small and pass through a filter paper?

• Chromatography

• Crystallisation

• Sublimation

• Centrifugation

• Distillation

324 Which of the following is not an application of centrifugation process of separation?

• Separation of cream from milk in dairies.

• Used in washing machines to squeeze out water from clothes.

• Used in laboratories to separate collodial particles from their solutions.

• Used in laboratories to separate a mixture of acetone and water.

• Used in diagnostic labs for blood and urine tests.

325. Which of the following statements is/are correct?

a. Emulsion and gel are both collodial solutions. b. Ultracentrifugation is used to separate the particles of a collodial solution. c. Pigments of natural colours can be separated by chromatography.

• Only a

• Only b

• Only c

• Only a and c

• All of these

326. Which of the following is/are correct regarding the statement- 'air is a mixture and not a pure substance'?

a. The amounts of gases present in air at different places varies. b. The properties of air are the properties of its constituents. c. The different gases present in air can be separated by the process of fractional distillation of liquid air.

• Only a

• Only b

• Only c

• Only a and c

• All of these

327. A mixture of n-hexane and n-heptane can be separated through the process of _____________ method.

• chromatography

• distillation

• crystallisation

• fractional distillation

• centrifugation


328 Which of the following is the criteria to use chromatography for separating components of a mixture?

• This method used to separate a mixture comprising of solutes that dissolve in the same solvent.

• This method is used for the separation of a mixture containing two miscible liquids that boil without decomposing and have a large difference between their boiling points.

• Two immiscible liquids are separated by this method.

• In case the difference in the boiling points of the liquids is less than 25 kelvin temperature, we use the chromatography method.

• This method is used as a separation and purification method that involves the precipitating of solid crystals from its saturated solution on cooling.

329.Which of following statements is/are correct?

a. When a beam of light is passed through a collodial solution, the path of light gets illuminated. b. When an electric current is passed through a colloidal solution, particles move towards the oppositely charged electrodes. c. When an electric current is passed through an electrolyte solution, particles move towards the oppositely charged electrodes.

• Only a

• Only b

• Only c

• Only a and b

• a, b and c

330Assertion (A) : The air is a compound containing oxygen, nitrogen, argon, carbon dioxide and water vapour in a fixed proportion according to their masses.

Reason (R) : A compound is a substance whose composition of the components is fixed Le; they combine together in a fixed ratio according to their masses.

 331. Assertion (A) :A solution is a homogeneous mixture of two or more substances.

Reason (R) : A solution has a solvent and a solute as its components.

 332. Assertion (A) : In a colloid, the size of solute particles is bigger than the particles of true solution but smaller than those of suspension.

 Reason (R) : Sand with particle size between 10" to 10 m dissolves in water to form colloidal solution that shows Tyndall effect. (1 Mark)

333.Assertion (A) : Chromatography is used to separate pigments from natural colours like chlorophyll.

 Reason (R) : Coloured components of a mixture can be separated by using an adsorbent on which they are adsorbed at different rates.

334.Assertion (A) : A mixture of acetone and water is separated by using simple distillation method. This method is used to separate two or more miscible liquids.

Reason (R) : Acetone, out of the two components has a lower boiling point and water has higher boiling point.

335. Assertion (A) : Rusting of iron is a chemical change.

Reason (R) : Rusting is a slow process in which the surface of iron is spoiled due to the action of oxygen and water on it.

 336.Assertion (A) :A solution of table salt in a glass of water is homogeneous.

 Reason (R) : A solution having different composition throughout is homogeneous.

337. Assertion (A): A mixture of acetone and methanol can be separated by fractional distillation. Reason (R) : The difference between their boiling points is very less.

 338. Assertion (A) : Impure benzoic acid can be purified by sublimation.

Reason (R) : Benzoic acid sublimes on heating.

 

339    An alloy is a mixture of a solid in ___________.

340.     A ___________substance is made of same kind of elements.

341.     A ___________is a homogenous mixture of two or more substances.

342.     Solubility of a gas always___________ with increase in temperature.

   343.   ___________are classified according to the state of dispersed phase and dispersion phase.

344.     A colloidal with liquid as both dispersed phase and dispersion medium is called

345.     A/ an___________ does not show Tyndall effect.

345. ___________is the principle of separation used in diagnostic labs for blood and urine tests.

347.  The separation of a mixture of camphor and sodium chloride involves the principle of ___________ to separate.

348.  Gas molecules at higher temperature have more___________ at lower temperature. 

349  ___________of air is used in the separation of Oxygen, liquid nitrogen and argon from air.

350.  A colloid with liquid as dispensed phase and gas as dispersion medium is___________.

351.A compound can be separated into constituent elements by ___________methods.

352.___________method is used to obtain the pure crystals of copper sulphate from its saturated solution.

353.  Boron, germanium and silicon are the best examples of______.

.354.An element is a kind of matter that cannot be separated into other kind of matter by any physical process.

355.Mixture is a substance in which two or more substances are mixed together in definite proportion.

356.  Solubility of gases in the liquids always increases with the increase in temperature.

357.   A solid sol has, both the dispersed phase and dispersion medium are liquid.

358. In evaporation, out of the two components of a mixture one has lower while the other has higher boiling point.

359.  Milk on mixing in water forms homogeneous solution.

360.  Paper chromatography is based on the principle of difference in the solubilities of the components to be separated.

361.Process of centrifugation is used in dairies and at home to separate butter from cream.

362.Process of sublimation is used to separate the mixture of sodium chloride and ammonium chloride.

363. Mixture of ethanol and water can be separated using simple distillation method.

364. Mixture of acetone and water is separated using distillation.

365.Crystallisation is used to separate salt from sea water.

366.Burning of wood is a physical change.

367.A compound is a substance composed of two or more elements, chemically combined together in a fixed proportion.

368.  Boron, silicon and germanium are non-metals.

369Which of the following is a pure substance?

1. Air

2. Distilled water

3. Steel

4. Brass


370Which of the following statements are true for pure substances?

(i) Pure substances contain only one kind of particles.

(ii) Pure substances may be compounds or mixtures.

(iii) Pure substances have the same composition throughout.

(iv) Pure substances can be exemplified by all elements other than nickel.

1. (i) and (ii)

2. (i) and (iii)

3. (iii) and (iv)

4. (ii) and (iii)


371Which of the following property does not prove that water is a compound?

1. Water is made up of two different elements (H and O). Which chemically combined with one another in a fixed proportion.

2. Water has fixed boiling point (b.p.).

3. The constituents of water cannot be separated by simple physical methods.

4. Distilled water and tap water have same taste and constituents.


372.Two elements X and Y combine to give a product Z. The correct statement about Z is

1. Z has more mass than that of X

2. Z has less mass than that of X

3. Z has less mass than that of Y

4. Z show same properties as that of X and Y

.

373.Two substances, A and B were made to react to form a third substance, A2BA2B according to the following reaction 2A+B→A2B2A+B→A2B. Which of the following statements concerning this reaction are incorrect?
(i) The product A2BA2B shows the properties of substance A and B.

(ii) The product will always have a fixed composition.

(iii) The product so formed cannot be classified as a compound.

(iv) The product so formed is an element.

1. (i), (ii) and (iii)

2. (ii), (iii) and (iv)

3. (i), (iii) and (iv)

4. (ii), (iii) and (iv)


374.Which of the following substances are homogeneous in nature?

(i) Ice

(ii) Wood

(iii) Soil

(iv) Air

1. (i) and (iii)

2. (ii) and (iv)

3. (i) and (iv)

4. (iii) and (iv)


375.Which of the following will not show Tyndall effect?

1. Smoke

2. Foam

3. Jelly

4. Salt solution


376 The method used to separate a dye from blue ink is

1. evaporation

2. sedimentation

3. crystallisation

4. filteration

377.The most suitable technique used to separate mixture of different gases from bulk of air can be

1. chromatography

2. sublimation

3. fractional distillation

4. centrifugation



378.Which of the following are chemical changes?

(i) Decaying of wood 

(ii) Burning of wood

(iii) Sawing of wood

(iv) Hammering of a nail into a piece of wood

1. (i) and (ii)

2. (ii) and (iii)

3. (iii) and (iv)

4. (i) and (iv)

380.Assertion
water is homogeneous.

Reason A solution having different composition throughout is homogeneous.

381. If both Assertion and Reason are true and reason is the correct explanation of Assertion.

382. If both Assertion and Reason are true but Reason is not the correct explanation of Assertion.

383. If assertion is true but Reason is false.

384. If assertion is false but reason is true.


385Assertion A mixture of sugar and benzoic acid can be separated by shaking with ether.

Reason Sugar is insoluble in water

386.Assertion True solutions exhibins Tyndall effect.

Reason Particles are very small in size.

387. If both Assertion and Reason are true and reason is the correct explanation of Assertion.

388.If both Assertion and Reason are true but reason is not the correct explanation of Assertion.

389. If Assertion is true but Reason is false.

340. If Assertion is false but Reason is true.

341Assertion Impure benzoic acid can be purified by sublimation.

Reason Benzoic acid sublimes on heating.

342.Assertion Chromatography can be used to separate a mixture of plant pigments.

Reason Chromatography is a process of separation of components of a mixture.

1. If both Assertion and Reason are true and Reason is the correct explanation of assertion.

2. If both Assertion and Reason are true but Reason is not the correct explanation of assertion.

3. If assertion is true but reason is false.

4. If assertion is false but reason is true.

343. Distinguish among the true solution, suspension and colloid in a tabular form under the following heads:

a. Stability

b. Filterability

c. Type of mixture

344. Give expression for the concentration of a solution. How will you prepare a 10% solution of glucose by mass in water?


345.Write your observations when the following processes take place:

1. An aqueous solution of sugar is heated to dryness.

2. A saturated solution of potassium chloride prepared at 608°C608°C is allowed to cool at room temperature.

3. a mixture of iron filings and sulphur powder is heated strongly.

4. A beam of light is passed through a colloidal solution.

5. Dilute HCl is added to the mixture of iron and sulphur.

346 Pond water contains sand grains, clay particles, salt, pieces of paper and some air bubbles. Select from amongst these, an example each of a solvent, solute, colloid and suspension.

347. Give one example of each of the following:

a. A solution of gas in liquid

b. A solution of two solids

c. A solution of two gases.


348You are provided with a mixture of napthalene and sodium chloride by your teacher. Suggest an activity to separate them with well-labelled diagram.

349.Give an example each for the mixture having following characteristics. Suggest a suitable method to separate the components of these mixtures.

350. A volatile and non-volatile components.

351.. Two volatile components with appreciate difference in boiling points. 

352.Two immiscible liquids.

353.One of the components changes directly from solid to gaseous state.

354.Two or more coloured constituents soluble in same solvent.


355. Write the steps involved in the process of obtaining pure copper sulphate from an impure sample.

356. Give any one application of this method.

357. Why is this technique better than simple evaporation to purify solids?

358. Draw a neat and labelled diagram of the apparatus used to separate components of blue-black ink. Name the process and state the principle involved.

359. Identify the physical and chemical changes from the following.

a. Burning of magnesium in air

b. Tarnishing of silver spoon

c. Sublimation of iodine

4. Electrolysis of water


360Classify each of the following as a physical or a chemical change. Give reasons.

1. Drying of a shirt in the sun.

2. Rising of hot air over a radiator.

3. Burning of kerosene in a lantern.

4. Change in the colour of black tea on adding lemon jiuce to it.

5. Churning of milk cream to get butter.





Answers
1b
2c
3d
4d
5c
6a
7b
8b
9b
10c
11a
12c
13d
14c
15b
16a
17heterogenous cenwtirfugaation
18.physically and chemically
19.wqter and chloroform
20.fractional distillation
21scayterung and Tyndall effect and colloid
22.c
23.a
24.b
25.d
26.d
27.d
28.b
29.c
30.b
31.c
32.d
33.b
34.b
35.d
36.d
37. (c)
38.(b)
39.(c)
40(c)
41.(a)
42.(b)
43. (a)
44.(a)
45. (d
)46. (b)
47.(c)
48. (b)
49. (a) 50 d 51c 52a 53c 54a 55a 56c 57b 58c 59b 60d 61c.62b 63c 64a 65 b 66c 67d 68d 69 c 70 a 71 a 72d 73d 74b 75c
76a 77a 78 c 79a 80 d
81c 82c 83 d 84d 85 d
86c 87 d 88d 89 d 90d
91c 92 d 93c 94 b 95 d
96.c 97a 98c 99c 100c
101c 102b 103b 104b 105d
106c 107d 108d 109b 110a
111c 112a113d 114b 115b
116a 117b 118b 119d 120b
121c 122c 123a 124a 125a
126a 127a 128a 129c 130a
131a 132b
133.(d)
134.(d)
135.(c)
136.(a)
Q37.(b)
138(a)
139.(d)
140.(d)
141..(b)
142(c)
143(c)
144.(d)
145(b)
146.(b)
147.(d)
148.(b)
149.(b)
150.(d)
151.(d)
152.(a)
153.(c)
154.(d)
155.(b)
156.(d)
157(a)
158.(b)
159(c)
160.(a)
161(b)
162.(c)
163.(b)
164.(b)
165c 166a 167b 168d 169d 170d 171b
172c 173b 174c 175d 176b
177b 178d 179 d
180. b. 181. b. 182 c. 183d. 184 c. 185 b. 186. c.
187. d. 188. d. 189 b. 190. a. 191. b. 192. b.
193 d.
194. c. 195. d. 196. c. 197. c. 198 d. 199. a.
200. d.
201. c. 202. d. 203. c. 204. b. 205. b. 206. c
. 207 b.
208. b. 209. d.
210 d
211b
212d
213a
214a
215a
216c
217d
218a
219a
220c
221b
222c
223a
224a
225c
226c
227a
228d
229a
230b
231a
232b
233d
234a
235c
236c
237d
238c
239a
240b
241c
242a
243d
244a
245d
246b
247d
248c
249a
250b
251c
252a
253b
254diffusion
255increases
256surface
257increasrs
258partickes
259low viscosity
260maximum.interdmediate,mininmum
261weakwr
262suimation
263up
264cooling
265zero
266melting point
267kinetic energy
268states
269decreases
270true
271false
272true
273true
274false
275 true
276false
277false
278true
279false
280false
281false
282true
283false
284false 285true 286a 287a 288c
289c 290b 291d 292a 293c 294a 295b 296a 297c 298c 299b 300b

301a
302a
303c
304c
305b
306d
307a
308c
309a
310b
311a
312c
313c
314b
315b
316a
317d
318d
319d
320b
321a
322d
323d
324d
325e
326e
327d
328a
329e
330onwards ni answers
Till
360

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