HEAT MCQ ICSE CLASS 8

Tick (✔) The correct choice amongest the following

1. When a bimetallic strip (brass and invar) is heated : (a) it remains straight (b) it bends with brass on convex side (c) it bends with invar on convex side (d) it does not have a definite shape

2. A bimetallic strip is not used in : (a) thermostat(b) pendulum clock(c) fire alarm(d) electric iron

3. In solids thermal expansion is of : (a) three types(b) four types(c) five types(d) all of these

4. Linear expansion does not depend on the : (a) nature of material (b) original length of the body (c) the increase in temperature (d) original surface area of the body

Answers

Tick (✔) The correct choice amongest the following

1. (b) it bends with brass on convex side

2. (b) pendulum clock

3. (a) three types

4. (d) original surface area of the body

WORKSHEET

Select the correct alternative 

(a) In evaporation

1. all molecules of liquid begin to escape out

2.  only the molecules at the surface escape out

3.  the temperature of liquid rises by absorbing heat from surroundings.

4.  the molecules get attracted within the liquid.

(b) The rate of evaporation of a liquid increases when :

1.  temperature of liquid falls

2.  liquid is poured in a vessel of less surface area

3.  air is blown above the surface of liquid

4.  humidity increases.

(c) During boiling or vaporization

1.  all molecules take part

2.  temperature rises

3.  no heat is absorbed

4.  the average kinetic energy of molecules increases.

(d) The boiling point of a liquid is increased by

1.  increasing the volume of liquid

2.  increasing the pressure, on liquid

3.  adding ice to the liquid

4.  decreasing pressure on liquid.

(e) Two rods A and B of the same metal, but of length 1 m and 2 m respectively, are heated from 0°C to 100°C. Then

1.  both the rods A and B elongate the same

2.  the rod A elongates more than the rod B

3.  the rod B elongates more than the rod A

4.  the rod A elongates, but the rod B contracts.

(f) Two rods A and B of the same metal, same length, but one solid and the other hollow, are heated to the same rise in temperature.Then

1.  the solid rod A expands more than the hollow rod B

2.  the hollow rod B expands more than the solid rod A

3.  the hollow rod B contracts, but the solid rod A expands

4.  both the rods A and B expand the same.

(g) A given volume of alcohol and the same volume of water are heated from the room temperature to the same temperature then.

1.  alcohol contracts, but water expands

2.  water contracts, but alcohol expands

3.  water expands more than alcohol

4.  alcohol expands more than water.

(h) The increase in length of a metal rod depends on

1.  the initial length of the rod only

2.  the rise in temperature only

3.  the material of rod only

4.  all the above three factors.

(i) The correct statement is

1.  Iron rims are cooled before they are placed on the cart wheels.

2.  A glass stopper gets tighten on warming the neck of the bottle.

3.  Telephone wires sag in winter, but become tight in summer.

4.  A little space is left between two rails on a railway track.

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Write True Or False

1. During boiling, the temperature of the liquid does not change.

2. A bimetallic strip is used in a thermostat.

3. The expansion in volume is called superficial expansion.

4. The iron girders of a bridge contract in summer and expand in winter.

Answers

Write True Or False

1. False

2. True

3. False

4. True

WORKSHEET

1. Write true or false for each statement

(a) Evaporation is rapid on a wet day.

Answer. False.

(b) Evaporation takes place only from the surface of liquid.

Answer. True.

(c) All molecules of a liquid take part in the process of evaporation.

Answer. False.

(d) Temperature of a liquid rises during boiling or vaporization

Answer. False.

(e) All molecules of a liquid take part in boiling.

Answer. True.

(f) Boiling is a rapid phenomenon.

Answer. True.

(g) All solids expand by the same amount when heated to the same rise in temperature.

Answer. False.

(h) Telephone wires are kept tight between the two poles in winter.

Answer. True.

(i) Equal volumes of different liquids expand by the different amount when they are heated to the same rise in temperature.

Answer. True.

(j) Solids expand the least and gases expand the most on being heated.

Answer. True.

(k) A mercury thermometer makes use of the property of expansion of liquids on heating.

Answer. True.

(l) Kerosene contracts on heating.

Answer. False.

Write true or false. Correct the false statements.

Question

1.Boiling causes cooling.

Answer:False.

Correct : Evaporation causes cooling.

Question

2.Wet clothes dry because the water in them boils to its vapour state.

Answer:False.

Correct : Wet clothes dry because the water in them evaporates to its vapour state.

Question

3.Boiling occurs in the whole volume of a liquid whereas evaporation occurs only at the surface of a liquid.

Answer:True

Question

4.Water evaporates at all temperatures.

Answer:True

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Select the Odd and Out Giving reason

1. Thermal expansion, boiling, superficial expansion, volume expansion.

2. Evaporation is fast, evaporation occurs at all temperatures, evaporation is energy supplied by surroundings, no bubbles are formed in evaporation.

3. Solids, wood, liquids, gases.

Answers

Select the Odd and Out Giving reason

1. Boiling : others are types of expansion

2. Evaporation is fast : is not a property of evaporations others are

3. Wood : others are three states of matter.

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Fill in The Blanks

1. Evaporation occurs at ...........................

2. In solids thermal expansion is of ........................., ......................... and ............................

3. ............................. is an expansion when a solid is heated there is a change in its volume.

4. A bimetallic strip is made from .........................which expand by different amounts when heated.

5. A ........................ is a metal pin or bolt used for fastening metal plates

Answers

Fill in The Blanks

1. any temperature

2. linear, superficial, cubical

3. cubical expansion

4. two thin strip of metal

5. rivet

WORKSHEET

2. Fill in the blanks 

(a) Boiling occurs at a fixed temperature.

(b) Evaporation takes place at all temperature.

(c) The molecules of liquid absorb heat from surroundings in evaporation.

(d) Heat is absorbed during boiling.

(e) Cooling is produced in evaporation.

(f) A longer rod expands more than a shorter rod on being heated to the same temperature.

(g) Liquids expand more than the solids.

(h) Gases expand more than the liquids.

(i) Alcohol expands more than water.

(j) Iron expands less than copper.

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Match The Columns

1. 1.Thermal expansion fast 2.Bimetallic strip  electric iron 3.Boiling sensation of hotness or coldness 4.Evaporation slow 5.Heat Gravesad’s ball and ring experiment

Answers

Match The Columns

1. 1.Gravesad’s ball and ring experiment

2.electric iron

3.fast

4.slow

5.sensation of hotness or coldness

WORKSHEET

3. Match the following

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Kinetic Theory of Matter MCQ ICSE CLASS 8

Tick (✔) The correct choice amongest the following

1. The quantity of matter present in a substance is called its : (a) weight(b) gram(c) mass(d) density

2. Which of the following substance undergoes sublimation ? (a) sodium chloride(b) ammonium chloride (c) sugar(d) sand

3. What is the correct term for the phase changes from solid to gas directly ? (a) sublimation(b) liquefaction(c) fusion(d) vaporization

4. Evaporation of a liquid can take place : (a) at its boiling point(b) at all temperatures(c) below its boiling point(d) at a fixed temperature

5. Which of the following is not matter ? (a) humidity(b) fog(c) blood(d) boiling point

Answers

Tick (✔) The correct choice amongest the following

1. (c) mass

2. (b) ammonium chloride

3. (a) sublimation

4. (c) below its boiling point

5. (d) boiling point

Worksheet

A. Choose the correct answer.

1. When this form of energy is supplied to a substance, its molecules move faster and

hence their kinetic energy increases. Name the form of energy.

(a) Wind energy (b) Heat energy

(c) Light energy (d) Electrical energy

2. What is the force of attraction that exists between similar kinds of molecules called?

(a) Force of interparticle (b) Force of crossparticle

(c) Force of interpath (d) Force of cohesion

3. The distance between the molecules of a substance is called the ______________.

(a) intermolecular force (b) cohesion space

(c) intermolecular distance (d) crossparticle space

4. The intermolecular forces are almost negligible; due to this the molecules are very

loosely packed. Which state of matter is being talked about?

(a) Light (b) Gas (c) Liquid (d) Solid

1. Matter

5. They have no fixed shape but fixed volume. They take the shape of the container

they are poured in. Which state of matter is being talking about?

(a) Liquid (b) Gas

(c) Solid (d) None of the above

Answers to Worksheet

A. 1. (b) 2. (d) 3. (c) 4. (b) 5. (a)

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Write True Or False

1. The intermolecular forces in gases are weaker than in solids.

2. Liquids take the shape of the vessel.

3. All the three states of matter cannot be interconverted into one another.

4. The kinetic theory of matter explains the physical difference between solids, liquids and gases.

5. During the inter-conversion of states of matter, mass undergoes a change.

Answers

Write True Or False

1. False

2. True

3. False

4. False

5. True

Worksheet

B. State whether the following statements are True or False. Correct the false statements.

1. The force of attraction that exists between different types of molecules is called

force of adhesion.

2. The intermolecular force of attraction is directly proportional to the intermolecular

space.

3. Due to strong intermolecular forces, molecules are bound together. This is why

solids have a fi xed shape and size.

4. Due to large space between the molecules, liquids can be compressed more easily

than solids.

5. Solid is that state of matter in which the constituent molecules are the most loosely

packed.

Answers to Worksheet

B. 1. True

2. False

The intermolecular force of attraction is directly proportional to the intermolecular

space. (inversely)

3. True

4. True

5. False

Solid is that state of matter in which the constituent molecules are the most loosely

packed. (Gas)

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Select the Odd and Out Giving reason

1. Solid, liquid, gas, evaporation.

2. Condensation, sublimation, matter, freezing.

3. Melting, boiling, fusion, mass.

4. Density, volume, area, shape.

5. Element, atom, molecule, sublimation

Answers

Select the Odd and Out Giving reason

1. Evaporation : others are three states of matter.

2. Matter : others are changes of the states.

3. Mass : others are processes

4. Shape : others are physical quantities

5. Sublimation : it is a process

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Fill in The Blanks

1. Three states of matter are .................. , .................. and .....................

2. A vapour on cooling changes into .................. and on further cooling changes into .................

3. The molecules (particles) of solid are .................. packed.

4. A substance in the .................. state, has definite .................. but no definite .....................

5. There are two types of molecular forces in nature, .................. and .....................

Answers

Fill in The Blanks

1. solid, liquid, gas

2. liquid, solid

3. tightly

4. liquid, volume, shape

5. force of cohesion, force of adhesion

Worksheet

C. Fill in the blanks.

1. ________________ is the smallest unit of matter (substance) which can exist

independently and retains all physical and chemical properties of that substance.

2. Kinetic theory of matter given in the year 1860 states that matter is composed of a

large number of small particles called atoms which are in _____________________.

3. The molecules of matter always exert an attractive force on each other which is

known as ____________________ force.

4. Due to strong molecular attraction between the molecules, ______________ does

not cause appreciable expansion in solids.

5. On supplying heat to the matter, the molecules gain energy and they start

________________ vigorously.

Answers to Worksheet

C. 1. Molecule 2. continuous motion 3. intermolecular

4. heating 5. vibrating

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Match The Columns

1. 1.Solids frost 2.Evaporation surface phenomenondry 3.Ice crystals Dry ice 4.Sublimation DeW drops 5.Condensation definite shape and a definite size

Answers

Match The Columns

1. 1.definite shape and a definite size

2.surface phenomenon

3.frost

4.dry ice

5.dew drops

WORKSHEET

D. Match the columns.

Column A Column B

1. Matter (a) They have a definite volume but not a fixed shape. 2. Solids (b) The intermolecular forces are the weakest.

3. Gases (c) Change of a substance from one physical

state to another.

4. Liquids (d) Anything that has mass and occupies space

5. Change of state (e) The molecules do not move, but only

vibrate about their mean position

Answers to Worksheet

D. 1. (d) 2. (e) 3. (b) 4. (a) 5. (c)

Water MCQ

CLASS 9

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CLASS 8

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CLASS 6