Question:
Name the process which can be used to separate a mixture of salt solution and sand.
Is Matter Around Us Pure?
Q 1.
What is the general name of the process by which tea-leaves are separated from prepared tea ?
Q 2.
Choose one term from the following which includes the other three :
aerosol,
emulsion,
colloid,
sol
Q 3.
Name the property of any one of the components which can be used for separating the following mixture : Salt and Camphor
Q 4.
What are the properties of a colloid?
Q 5.
Name the property of one of the constituents which can be used to separate a mixture of salt and iodine
Q 6.
What are the physical states of dispersed phase and dispersion medium of a cloud?
Q 7.
What are the physical states of dispersed phase and dispersion medium of a fog?
Q 8.
Classify the following as physical or chemical changes :
(i) Cooking of food
Q 9.
Name any two solid substances whose mixture can be separated by sublimation.
Q 10.
To make a saturated solution, 36 g of sodium chloride is dissolved in 100 g of water at 293K. Find its concentration at this temperature.
Q 11.
Which of the following is a sol ?
Shaving cream,
Milk,
Fog,
Soap solution,
Hairspray
Q 12.
Which of the following will show Tyndall effect ? Why ?
(a) Salt solution
(b) Starch solution
(c)Milk
Q 13.
(a) What is meant by a solution ? Give two examples of solutions.
(b)What is a suspension ? Give two examples of suspensions.
(c)
Q 14.
List the points of differences between homogeneous and heterogeneous mixtures.
Q 15.
State the differences between compounds and mixtures.
Q 16.
What is meant by solute and solvent?
Q 17.
Describe sieving method.
Q 18.
Identify the following as mixture or compound.
(i) blood
(ii) common salt
(iii) sugar
(iv) brass
Q 19.
What is an emulsion? Give examples
Q 20.
Name a non-metal which is a good conductor of electricity.
Q 21.
Name the property :
(a) which allows metals to be hammered into thin sheets.
(b)
Q 22.
Name the source from which nitrogen and oxygen are obtained on a large scale.
Q 23.
Which technique can be used to detect and identify traces of poison present in the stomach wash of a person ?
Q 24.
On the basis of composition, how matter is classified?
Q 25.
What are aqueous solutions?
Q 26.
What is an unsaturated solution?
Q 27.
What is saturated solution? Explain with an example.
Q 28.
What are suspensions? Explain with an example.
Q 29.
What are the properties of suspensions?
Q 30.
What do you mean by strength of the solution?
Q 31.
What are different ways to separate solid mixtures?
Q 32.
What are the reasons for separating the constituents of a mixture?
Q 33.
A good method to separate alum (phitkari) from impure samples is
(a) Filtration
(b) Sedimentaion
(c) Crystallization
(d) Sublimation
Q 34.
Define Brownian movement in colloids.
Q 35.
Name the following :
(a) a lustrous liquid metal.
(b) a liquid non-metal
(c) a metal which can be cut with a knife
(d) a non-metal which is good conductor of electricity.
(e) an element which melts when kept on the palm.
(f) the best conductor of heat.
Q 36.
Give examples of liquids that are
(i) completely miscible
(ii) partially miscible
(iii) practically immiscible
Q 37.
Which of the following is a mixture ?Salt, Air, Water, Alum, Sugar
Q 38.
How much water should be mixed with 12 mL of alcohol so as to obtain 12 % alcohol solution ?
Q 39.
A 5 per cent sugar solution means that:
(a)5 g of sugar is dissolved in 95 g of water.
(b)5 g of sugar is dissolved in 100 g of water.
Choose the correct answer.
Q 40.
Name the process you would use to separate ammonium chloride from a mixture of sodium chloride and ammonium chloride.
Q 41.
What type of magnet is fitted on a crane to separate scrap iron objects from a heap of waste materials in factories ?
Q 42.
Name one pair of liquids which can be separated by using a separating funnel.
Q 43.
State whether the following statements are true or false :
(a) Alcohol can be separated from a mixture of alcohol and water by a separating funnel.
(b) Salt and water can be recovered from an aqueous salt solution by the process of evaporation.
Q 44.
(a) Name the process by which common salt is obtained from sea-water.
(b) Name the process by which common salt is purified.
Q 45.
What are the characteristics exhibited by a pure substance?
Q 46.
What is meant by Solubility?
Q 47.
Why do fish go in deep waters during day light?
Q 48.
What principle is applied in centrifugation? Give examples where this method is applied to separate mixtures.
Q 49.
Who used the term 'element' first time?
Q 50.
What are the differences and similarities between concentration and solubility?
