MCQ PRACTICE 1

Welcome to your Ncert - class 9- science - Chapter 1 – Matter in Our Surroundings 1

The heat gained or lost during a change of state from solid to liquid or from liquid to solid is called the latent heat of .......

fusion

vaporisation

condensation

freezing

None

Latent heat is evolved during the transformation of liquids into solids.

How will you explain this statements?

Heat does not get absorbed nor released

Heat is released and temperature decreases

Heat is absorbed and temperature increases

None of the above

None

The process by which molecules undergo a spontaneous transition from the liquid phase to the gaseous phase is called as:

freezing

condensation

evaporation

sublimation

None

Which of the following is the BEST indicator of the actual amount of water vapour in the air?

Saturation vapour pressure

Dew point temperature

Air temperature

Relative humidity

None

The temperature of melting ice remains constant for some time even if we continue to supply heat to the beaker. This is because of the heat energy ?

is used to bring the particles of matter closer

is used to overcome the forces of attraction between the particles

is radiated out

is used to change the pressure on the particles

None

During change of state of matter, the temperature remains the same due to:

less supply of heat

lattice energy

loss of heat

latent heat

None

Match Column I with Column II and select the correct option from the codes given below

Column I	Column II
(a) Drying of clothes on a windy day	(i) Time taken for evaporation increases
(b) Liquefaction of gases	(ii) Decreasing pressure and increasing temperature
(c) Change in state of dry ice from solid to gas	(iii) Increasing pressure and decreasing temperature
(d) Less cooling effect of sweating in coastal areas	(iv) Rate of evaporation increases

a - (i), b - (ii), c - (iii), d - (iv)

a - (iv), b - (iii), c - (i), d - (ii)

a - (iv), b - (iii), c - (ii), d - (i)

a - (iii), b - (iv), c - (ii), d - (i)

None

Select the correct alternative

The molecules can move freely anywhere in_____ state.

solid

gaseous

liquid

none of the above

None

Which one of the following statement is correct ?

Both boiling and evaporation are bulk phenomena.

Both boiling and evaporation are surface phenomena.

Boiling is a bulk phenomenon, but evaporation is a surface phenomenon

Boiling is a surface phenomenon, but evaporation is a bulk phenomenon

None

10.

Which among the following have moderate intermolecular forces?

Equal in liquids and gases both

Gases

Solids

Liquids

None

11.

Evaporation of a liquid takes place at:

all temperatures.

any temperature lower than its boiling point.

a fixed temperature higher than its boiling point.

a fixed temperature and pressure.

None

12.

Evaporative cooling is the phenomenon _____________.

none of these

in which molecule of liquid with high kinetic energy evaporates quickly, leaving behind the particle of less kinetic energy

in which density of liquid changes

in which molecule of liquid with low kinetic energy evaporates quickly, leaving behind the particle of high kinetic energy

None

13.

Identify the correct statement about gases:

Gases can not flow.

Gases can not be compressed easily.

Gases occupy the entire space of the container.

Gases have definite shapes.

None

14.

Which of the following is a correct statement?

The inter-particle force of attraction between the molecules in a liquid is either more or less when compared to solids.

The inter-particle force of attraction between the molecules in a liquid is more when compared to solids.

The inter-particle force of attraction between the molecules in a liquid is less when compared to solids.

There is no inter-particle force of attraction between the molecules in a liquid.

None

15.

The molecules:

in a liquid move within its boundary.

in a gas move only within its boundary.

in a solid move freely within its boundary.

in solid, liquid and gas move freely anywhere.

None

16.

Statement I : Evaporation causes cooling.

Statement II: Particles of liquid absorb energy from the surrounding to regain the energy lost during evaporation.

Both statements I and II are true, statement II is not the correct explanation for statement I.

Statement I is true and statement II is false.

Both statements I and II are true, statement II is correct explanation for statement I.

Statement I is false and statement II is true.

None

17.

What is the effect on the chemical and physical properties of water when the temperature is changed?

The chemical properties of water remain the same but the physical state changes with a temperature change.

There is no effect on the chemical or physical properties of water when the temperature is changed.

The chemical properties of water change with temperature change but physical properties remain the same.

Both chemical and physical properties of water change with a temperature change.

None

18.

Which one of the following statement is correct in respect of fluids?

Only gases behave as fluids

Only liquids behave as fluids

Gases and solids behave as fluids

Gases and liquid behave as fluids

None

19.

A fully inflated balloon goes higher in the atmosphere, so what will be the pressure outside and inside the balloon respectively.

Increases, Decreases

Increases, Remains constant

Decreases, Increases

Decreases, Remains constant

None

20.

The percentage of para hydrogen in ordinary hydrogen increases when?

Temperature is lowered

None

Temperature is increased

Pressure is increased and temperature is decreased

None

Chapter 1 Matter In Our Surroundings

Chapter 2 – Is Matter Around Us Pure

Chapter 3 – Atoms and Molecules

Chapter 4 – Structure of the Atom

Curriculum

Ncert Class9-Chemistry-Science

Chapter 1 Matter In Our Surroundings

Chapter 2 – Is Matter Around Us Pure

Chapter 3 – Atoms and Molecules

Chapter 4 – Structure of the Atom

MCQ PRACTICE 1