MCQ PRACTICE 1

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

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

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

How will you explain this statements?

None of the above

Heat is released and temperature decreases

Heat is absorbed and temperature increases

Heat does not get absorbed nor released

None

Evaporation of a liquid takes place at:

any temperature lower than its boiling point.

a fixed temperature and pressure.

all temperatures.

a fixed temperature higher than its boiling point.

None

Evaporative cooling is the phenomenon _____________.

none of these

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

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

None

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

Saturation vapour pressure

Air temperature

Relative humidity

Dew point temperature

None

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

Gases and solids behave as fluids

Only liquids behave as fluids

Only gases behave as fluids

Gases and liquid behave as fluids

None

Which of the following is a correct statement?

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 either more or less 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

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 false and statement II is true.

Statement I is true and statement II is false.

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

None

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 .......

condensation

freezing

vaporisation

fusion

None

10.

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

loss of heat

less supply of heat

latent heat

lattice energy

None

11.

Select the correct alternative

The molecules can move freely anywhere in_____ state.

liquid

solid

gaseous

none of the above

None

12.

Identify the correct statement about gases:

Gases occupy the entire space of the container.

Gases can not be compressed easily.

Gases can not flow.

Gases have definite shapes.

None

13.

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

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

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

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

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

None

14.

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

15.

The percentage of para hydrogen in ordinary hydrogen increases when?

Pressure is increased and temperature is decreased

Temperature is increased

None

Temperature is lowered

None

16.

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

Decreases, Increases

Increases, Decreases

Increases, Remains constant

Decreases, Remains constant

None

17.

Which among the following have moderate intermolecular forces?

Equal in liquids and gases both

Liquids

Gases

Solids

None

18.

Which one of the following statement is correct ?

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

Both boiling and evaporation are bulk phenomena.

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

Both boiling and evaporation are surface phenomena.

None

19.

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

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

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

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

None

20.

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 overcome the forces of attraction between the particles

is radiated out

is used to change the pressure on the particles

is used to bring the particles of matter closer

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