Questions

QUESTIONS

1. Solubility of a solid depends on which of the following factors?

I. The kind of solid

II. II. Pressure

III. Temperature

IV. IV. The kind of solvent

A) I-III B) II-III C) III-IV D) I-II-III E) I-III-IV

2. Which of the following effects increase the rate of dissolving of sugar in water?

I. To grind the sugar

II. To apply pressure on water

III. To stir sugar

IV. To heat water

A) Only I B) I-II C) II-III D) I-II-IV E) I-III-IV

3. You boil away a clear liquid until a solid remains. What can you say about this liquid?

A) It is a suspension B) It is a solution

C) It is a emulsion D) It is a pure liquid

E) It is a heterogenous mixture

4. I. Water dissolves table salt but does not dissolve iodine and naphthalene

II. Carbon tetrachloride dissolves iodine and naphthalene but does not dissolve table salt

According to given information which of the following mixtures can be separated either by using water or by using carbon tetrachloride?

I. Table salt-iodine

II. Table salt- naphthalene

III. Naphthalene-iodine

A) Only I B) Only II C) I and II D) II and III E) I,II and III

5. A mixture which contains iron fillings, naphthalene, sugar and salt is separated into its components. What is the correct order of the separation methods?

I. Filtration II. Fractional crystallization

III. Dissolving in water IV. Separation by using a magnet

A) I-II-III-IV B) IV-III-I-II C) IV-III-II-I

D) I-III-IV-II E) III-I-IV-II

6. At 25 0C X is solid, Y and Z are liquids.

X is dissolved in Y but does not dissolve in Z.

Y and Z mixture is homogenous.

According to the given information:

I. Y and Z mixture can be separated by the use of density difference

II. X-Z mixture can be separated by filtration.

III. X–Y mixture can be separated by the difference in density.

which of the above statements are correct?

A) Only I B) Only II C) I-III D) II-III E) I,II and III

• 1. How would you separate a mixture containing nickel dust, pieces of straw and sand. Write step by step.

• 2. Describe two methods for the separation of rice and naphthalene mixture other than picking up and sieving. (Naphthalene is less dense than water and insoluble in it)

Substance Melting Point (0C) Boiling Point (0C)

X 60 75

Y -5 250

Z 210 716

Q 2 81

3. Melting and boiling points of four substancese given below.

A) Which substance(s) would be liquid at 25 (0C)?

B) Which solid-solid mixture at room temperature can be separated by the use of