Is Matter Around Us Pure

Chapter 2


MULTIPLE CHOICE QUESTIONS: 

1. Mixture are constituted by more than one kind of pure form of matter, known a ____.

a) Texture

c) Substance

b) Solution

d) Component

Ans. c) Substance


2. 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

Ans. d)Its composition may vary 


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

a) Ice

c) Iron

b) Mercury

d) All of these 

Ans. d) All of these


4. The components of water can be separated by 

a) Physical methods

b) Chemical methods

c) Both

d) They can't be separated

Ans. b) Chemical methods 


5. Camphor can be purified by:

a) Distillation

c) Sedimentation

b) Filtration

d) Sublimation

Ans. d)Sublimation


6. The process used to separate oil and water is:

a) Distillation

b) Sublimation

c) Separatingfunnel 

d) chromatography

Ans. c) Separatingfunnel


7. Filtration can be used to separate:

a) Solids from solids

b) Liquids from solids 

c)Liquids from liquids

d) Liquids from gases

 Ans. b)Liquids from solids


8. One common method to used separate dyes is:

a) Filtration

b) Distillation 

d) Conductivity

c) Chromatography

Ans. c)Chromatography


9. Mixture can be

a) homogeneous 

b) heterogeneous

c) Both (a) and (b)

d) pure substance 

Ans. c) Both (a) and (b)


10. What is true about homogeneous mixture?

a) Homogeneous mixture is the mixture of two or more than two components.

b) In homogeneous mixture the composition and properties are uniform throughout the mixture

c) both (a) and (b)

d) none of the above 

Ans. c) both (a) and (b)


11. A ____ is a substance composed of twoor more elements, chemically combined withone another in a fixed proportion.

a)compound

b) Matter

d)Alloy

c) Mixture

Ans. a) compound


12. Dissolved sodium chloride can be separated from water by ____.

a) Chemical process 

b) Physical process

c) Chemical process of extraction 

d) Physical process of evaporation

Ans. d) Physical process of evaporation 


13. Mixture of two or more metals, or metals and non-metals called as ____.

a) Alloy

c) Mixture

b) Solution

d)Metallic mixture 

Ans. a) Alloy


14. Distillation is a good separation technique for:

a)Solids

b)Liquids

c)Solid alloys 

d)Gases

Ans. b)Liquids 


15. Which of the following is heterogeneous mixture?

a) Air

b) Tincture of iodine

c) Sugar solution 

d) milk

Ans. d) milk


16. Alloy cannot be separated by ____ method 

a) Chemical

c) Extraction

b) Evaporation

d) Physical

Ans. d) Physical


17. Component present in large amount in solution called ____.

a) Solute

b) Sugar

c) Solvent

d) Mixture

Ans. c) Solvent


18. The component of solution that dissolved in solvent called ____.

a) Solute

b) Sugar

c) Solvent

d) Mixture

Ans. a) Solute


19. When no more solute can be dissolved in solution at given temperature is called ____.

a) Homogenous b) Heterogeneous

c) Saturated god) d) Unsaturated

Ans. c) Saturated


20. 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 

Ans. c) corrosion and it is a chemical change



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

a) Sodium

b) Potassium 

d) Bromine

c) Mercury

Ans. c) Mercury


22. Non uniform compositions of solutions called ____ solutions.

a) Mixture

b) Texture

c) Homogenous 

d) Heterogeneous

Ans. d) Heterogeneous


23. The amount of the solute present in the saturated solution at this temperature is called its ____.

a) Unsaturation

b) Diffusion

c) Collusion 

d) Solubility

Ans. d) Solubility


24. Which of the following is not physical changes?

a) Melting of iron metal

b) Rusting of iron

c) Bending of an iron rod 

d) Drawing a wire of iron metal

Ans. b) Rusting of iron


25. 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 solution

Ans. b) Unsaturated solution


26. Homogenous solution may separated by ____.

a) Chemical process

b) Physical process

c) filtration

d) Physical process of evaporation

Ans. a) Chemical process


27. Uniform compositions of solutions called ____ solutions.

a) Mixture

b) Texture

c) Homogenous 

d) Heterogeneous

Ans. c) Homogenous


28. Which of the following methods would you use to separate cream from milk? 

a) Fractional distillation

b) Distillation

c) Centrifugation

d) Filtration

Ans. c) Centrifugation


29. What will you observe when a mixture of iodine and salt is heated in a chine dish 

a) Iodine is left behind in the china dish. 

b) The mixture starts melting.

c) Salt is left behind in the china dish. 

d) No change in the china dish is observed

Ans. c) Salt is left behind in the china dish.


30. Name the mixture whose particles are large enough to scatter light. 

a) Colloid

b) True solutions

c) Homogeneous solution 

d) All of the above

Ans. a) Colloid


31. Mercury and bromine are both 

a) liquid at room temperature

b) solid at room temperature

c) gases at room temperature 

d) both (a) and (b) mile

Ans. a) liquid at room temperature 


32. Boron and carbon are

a) metalloids

b) metalloid and non-metal respectively

c) metal 

d) non-metal and metalloid respectively 

Ans. b) metalloid and non-metal respectively 


33. In a water-sugar solution

a) water is solute and sugar is solvent

b) water is solvent and sugar solvent is solute

c) water is solute and water is also

d) none of these 

Ans. b) water is solvent and sugar is solute


34. What is the principle behind the process of centrifugation?

a) Denser particles are forced to the bottom and lighter particles stay at the top when spun rapidly

b) Particles are separated based on the difference in colour

c) Particles are separated based on the difference in temperature

d) Lighter particles are forced to the bottom and denser particles stay at the top when spun rapidly

Ans. a) Denser particles are forced to the bottom and lighter particles stay at the top when spun rapidly


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

a) Unsaturation

b) Diffusion

c) Collusion d) centrifugation

Ans. d) centrifugation


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

a) Precipitation

b) Sublimation

c) Chromatography 

d) Cetrifugation 

Ans. b) Sublimation


37. 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 

Ans. b) Sol is a solid-liquid colloid and gel is liquid solid colloid


38. 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 ____.

a) Fractional distillation called

b) Sublimation

c) Separatingfunnel 

d) chromatography

Ans. a) Fractional distillation


39. 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

c) a molecule

b) an element

d) a mixture

Ans. b) an element


40. 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 

Ans. b) Immiscible liquids


41. 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

Ans. d) Concentration of a solution 


42. When light is passed through water !containing a few drops of milk, it shows a bluish tinge. This is due to the scattering of light by milk and the phenomenon is I called ____.

a) Crystallisation b) Tyndall effect

c) Chromatography d)None of these

Ans. b) Tyndall effect 


43. In the 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 

Ans. b) iodine is the solute and alcohol is the solvent


44. A component present in lesser quantity in solution called____.

a) Solute

b) Sugar

c) Solvent

d) Mixture

Ans. a) Solute


45. 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

Ans. d) Suspensions



Type By- Bikash Bora