Class 9 Practice Level 2 – Set 1 - Matter in Our Surrounding

Total questions: 25

What is latent heat?

Topic: Latent Heat

Heat required to change the state of a substance

Heat required to increase the temperature of a substance

Heat lost during cooling

Heat gained during heating

None

What happens to the temperature of a substance during the phase change?

Topic: Changes of State

It increases

It decreases

It remains constant

It fluctuates

None

Which of the following substances undergoes sublimation?

Topic: Sublimation

Ice

Dry ice (solid CO₂)

Water

Salt

None

What effect does increased surface area have on the rate of evaporation?

Topic: Evaporation

Increases it

Decreases it

No effect

First increases, then decreases

None

Which of the following is an example of a liquid turning into a gas at room temperature?

Topic: States of Matter

Boiling water

Evaporation of water from a pond

Melting of ice

Freezing of water

None

What happens to the pressure of a gas if its volume decreases while keeping temperature constant?

Topic: Gas Pressure

Pressure increases

Pressure decreases

Pressure remains the same

Pressure becomes zero

None

Which of the following conditions is most likely to cause condensation?

Topic: Condensation

High temperature and high humidity

Low temperature and low humidity

High temperature and low humidity

Low temperature and high humidity

None

What happens to the boiling point of water at higher altitudes?

Topic: Boiling Point

Increases

Decreases

Remains the same

First increases, then decreases

None

When ice melts to form water, what type of change occurs?

Topic: Changes of State

Physical change

Chemical change

Both physical and chemical change

Neither physical nor chemical change

None

10.

Which of the following has the highest kinetic energy?

Topic: Temperature

Ice at 0°C

Water at 0°C

Water at 100°C

Steam at 100°C

None

11.

Which of the following processes involves both a change in state and the release of energy?

Topic: Interconversion of States of Matter

Evaporation

Melting

Condensation

Sublimation

None

12.

Diffusion occurs fastest in which of the following states of matter?

Topic: Diffusion in Different States of Matter

Solid

Liquid

Gas

Plasma

None

13.

Which of the following best describes latent heat of vaporization?

Topic: Latent Heat of Vaporization

The heat energy required to change a liquid into a gas at its boiling point

The heat energy required to change a solid into a liquid at its melting point

The heat energy required to change a gas into a liquid at its condensation point

The heat energy required to increase the temperature of a liquid by 1°C

None

14.

What happens to the boiling point of water when the pressure is increased?

Topic: Effect of Pressure on Boiling Point

It decreases

It increases

It remains the same

It fluctuates

None

15.

What is the melting point of ice at standard atmospheric pressure?

Topic: Melting Point

0°C

25°C

50°C

100°C

None

16.

What happens to the particles of a substance during freezing?

Topic: Changes of State

They lose energy and move closer together

They gain energy and move further apart

They stop moving

They become larger

None

17.

Why do liquids have a definite volume but no definite shape?

Topic: Properties of Liquids

Because of weak intermolecular forces

Because of strong intermolecular forces

Because particles can move past each other

Because particles are fixed in position

None

18.

Which state of matter is most compressible?

Topic: Compressibility

Solid

Liquid

Gas

Plasma

None

19.

Plasma is most commonly found in which of the following?

Topic: Plasma

Earth's atmosphere

The Sun

Icebergs

Oceans

None

20.

Why does water boil at a lower temperature at higher altitudes?

Topic: Boiling Point and Pressure

Because atmospheric pressure is higher

Because atmospheric pressure is lower

Because temperature is lower

Because humidity is higher

None

21.

Which of the following conditions will increase the rate of evaporation?

Topic: Effect of Temperature on Evaporation

Lowering the temperature

Increasing the surface area

Increasing humidity

Decreasing wind speed

None

22.

What is the latent heat of fusion?

Topic: Latent Heat of Fusion

The energy required to melt a solid at its melting point

The energy required to evaporate a liquid at its boiling point

The energy required to condense a gas into a liquid

The energy required to freeze a liquid at its freezing point

None

23.

What happens to the volume of a gas when it is heated at constant pressure?

Topic: Effect of Temperature on States of Matter

It decreases

It remains the same

It increases

It fluctuates

None

24.

Which of the following substances undergoes sublimation?

Topic: Sublimation

Sodium chloride

Naphthalene

Ice

Water

None

25.

What is the main difference between boiling and evaporation?

Topic: Boiling and Evaporation

Boiling occurs only at the surface; evaporation occurs throughout the liquid

Evaporation occurs only at the surface; boiling occurs throughout the liquid

Both occur only at the surface

Both occur throughout the liquid

None

1 out of 25

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Class 9 Practice Level 2 – Set 1 - Matter in Our Surrounding

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