Chemistry (Y8) End of Years Revision

Question 1

What is the definition of a soluble substance?

Answer 1

A soluble substance is one that can be dissolved in a solvent.

Question 2

True or False: An insoluble substance cannot dissolve in a solvent.

Answer 2

True

Question 3

Fill in the blank: A __________ is a homogeneous mixture of two or more substances.

Answer 3

solution

Question 4

What is residue?

Answer 4

Residue is the solid material that remains after a liquid has been removed or has evaporated.

Question 5

What is the process of filtration used for?

Answer 5

Filtration is used to separate solids from liquids or gases using a filter medium.

Question 6

True or False: Evaporate means to convert a liquid into vapor.

Answer 6

True

Question 7

What is crystallization?

Answer 7

Crystallization is the process of forming solid crystals from a solution.

Question 8

Multiple Choice: Which of the following is NOT a characteristic of a solution? A) Homogeneous B) Variable composition C) Clear D) Stable

Answer 8

B) Variable composition

Question 9

What happens during the evaporation process?

Answer 9

During evaporation, the liquid phase of a substance changes into vapor, often leaving behind solid residue.

Question 10

Fill in the blank: A substance that does not dissolve in water is considered __________.

Answer 10

insoluble

Question 11

What is the main purpose of crystallization in chemistry?

Answer 11

The main purpose of crystallization is to purify a substance by forming pure solid crystals.

Question 12

True or False: All soluble substances can dissolve in any solvent.

Answer 12

False

Question 13

What is the key difference between soluble and insoluble substances?

Answer 13

The key difference is that soluble substances can dissolve in a solvent, while insoluble substances cannot.

Question 14

Multiple Choice: Which process can be used to separate a solid from a liquid in a mixture? A) Evaporation B) Filtration C) Crystallization D) All of the above

Answer 14

D) All of the above

Question 15

What is a saturated solution?

Answer 15

A saturated solution is one that contains the maximum amount of solute that can be dissolved at a given temperature.

Question 16

Fill in the blank: The solid that remains after a solution is filtered is called the __________.

Answer 16

residue

Question 17

True or False: Solutions can be composed of gases.

Answer 17

True

Question 18

What role does temperature play in the solubility of a substance?

Answer 18

Temperature can affect the solubility of a substance, typically increasing solubility in solids and decreasing it in gases.

Question 19

Multiple Choice: Which process involves cooling a solution to form solid crystals? A) Filtration B) Evaporation C) Crystallization D) Dissolution

Answer 19

C) Crystallization

Question 20

What is the definition of a solvent?

Answer 20

A solvent is a substance that dissolves a solute, resulting in a solution.

Question 21

What is the process called when a solid turns directly into a gas?

Answer 21

Sublimation

Question 22

True or False: Melting is the change of state from liquid to gas.

Answer 22

False

Question 23

Fill in the blank: The change from gas to liquid is known as __________.

Answer 23

Condensation

Question 24

Which of the following is NOT a change of state: a) freezing, b) boiling, c) dissolving?

Answer 24

c) dissolving

Question 25

What is the term for the change of state from liquid to solid?

Answer 25

Freezing