Q: Question 3If an object weighs 6 N on earth what will be its weight on moon? What will be the change in its mass?

The weight of body on moon will be 1 N i.e. [6N x 16\dfrac{\text{1}}{\text{6}}61] because the weight of body is 16\dfrac{\text{1}}{\text{6}}61 times lighter on the moon than it is on earth.There will be no change in its mass because mass of a body remains constant irrespective of its place.

Question 1

Question 3If an object weighs 6 N on earth what will be its weight on moon? What will be the change in its mass?

Accepted Answer

The weight of body on moon will be 1 N i.e. [6N x 16\dfrac{	ext{1}}{	ext{6}}61​] because the weight of body is 16\dfrac{	ext{1}}{	ext{6}}61​ times lighter on the moon than it is on earth.There will be no change in its mass because mass of a body remains constant irrespective of its place.

Question 2

Question 7Define:(a) Solid(b) Liquid(c) GasGive two examples of each type.

Accepted Answer

(a) Solid — A solid is that state of matter which has a definite shape and a definite volume. The two examples are gold, wood.(b) Liquid — A liquid is that state of matter which has a definite volume but no definite shape. The two examples are water, alcohol.(c) Gas — A gas is that state of matter which has neither a definite shape nor a definite volume. The two examples are hydrogen, oxygen.

Question 3

Question 9(a) Define interconversion of states of matter.(b) Why do solids, liquids and gases differ in their physical state?(c) Under what conditions do solids, liquids and gases change their state?

Accepted Answer

(a) The phenomenon of change of one state of matter into another and then back to the original state without any change in its chemical composition, is called interconversion of states of matter. It occurs due to change in temperature and pressure.(b) Solids, liquids and gases differ in their physical state due to difference in their intermolecular space and intermolecular forces of attraction.Solids have negligible intermolecular space as the molecules are closely packed and the force of attraction is maximum. In liquids the molecules are less tightly packed as compared to solids, so the intermolecular space is larger and force of attraction is weaker. In gases the molecules are far apart so the intermolecular space is very large and the force of attraction is the least.(c) Solids, liquids and gases change their state by change in temperature and by applying pressure.

Question 4

Question 11Fill in the blanks:(a) Air is a matter because it has ............... and ............... and it can be ............... .(b) The molecules are made up of ............... .(c) The quantity of matter in an object is called its ............... .(d) The state of matter with definite volume and definite shape is called ............... .(e) The substances which can flow are called ............... .

Accepted Answer

(a) mass, volume, compressed(b) atoms(c) mass(d) solid(e) fluids

Question 5

Question 12Name the terms for the following:(a) The change of a solid into liquid.(b) The force of attraction between the molecules of matter.(c) The particles of matter which may or may not have independent existence.(d) The process due to which a solid directly changes into its vapours.(e) The change of vapour into a liquid.

Accepted Answer

(a) Melting(b) Intermolecular force of attraction(c) Atom(d) Sublimation(e) Condensation

Question 6

Question 13Classify the following into solid, liquid and gas:Coal, kerosene, wood, oxygen, sugar, blood, water vapour, milk, wax.

Accepted Answer

SolidLiquidGasCoalkeroseneoxygenWoodbloodwater vapourSugarmilk Wax

Question 7

Question 3Each of the three states of matter has mass. Explain with the help of simple experiments that each state of matter has mass.

Accepted Answer

SolidsProcedure — A solid placed on the scale, causes the scale to tilt towards one side.Conclusion — The scale tilts due to the mass of the solid, hence all solids have mass.LiquidsProcedure — A liquid placed on the scale, causes the scale to tilt towards one side.Conclusion — The scale tilts due to mass of the liquid, hence all liquids have mass.GasesProcedure — A balloon placed on the scale, causes the scale to tilt towards one side.Conclusion — The scale tilts due to mass of the gas, hence all gases have mass.

Question 8

Question 6Differentiate the general properties of solids, liquids, and gases in the form of a table with reference to-(a) Mass(b) space(c) Volume(d) shape(e) compressibility(f) density(g) free surfaces(h) diffusion

Accepted Answer

CharacteristicsSolidsLiquidsGasMassHave massHave massHave massSpaceOccupies spaceOccupies spaceOccupies spaceVolumeA definite volumeA definite volumeNo definite volumeShapeA definite shapeNo definite shapeNo definite shapeCompressibilityNo compressibilitySlight CompressibilityHigh compressibilityDensityHigh DensityLess densityLeast densityFree SurfaceAny number of free surfacesOne upper free surfaceNo free surfacesDiffusionNo diffusibilitySlight diffusibilityHigh diffusibility

Question 9

Question 8Give a reason why-(a) Solids have a definite volume and a definite shape(b) Liquids have a definite volume but no definite shape(c) Gases have no definite volume and no definite shape.

Accepted Answer

(a) Solids have negligible intermolecular space as the molecules are closely packed and the force of attraction is maximum. This arrangement of molecules gives them a definite volume and a definite shape.(b) In liquids the molecules are less tightly packed as compared to solids, so the intermolecular space is larger and force of attraction is weaker. This gives them a definite volume but no definite shape.(c) In gases the molecules are far apart so the intermolecular space is very large and the force of attraction is the least. Hence, gases have no definite volume and no definite shape.

Question 10

Question 10Describe simple experiments to show that —(a) Particles of matter have intermolecular attraction.(b) Particles of matter are closely packed in solids and less in liquids.

Accepted Answer

(a) Simple experiment to show that particles of matter have intermolecular attraction:Procedure : Globules of mercury are placed in a petri dish and kept at a distance. Then the petri dish is shaken, and the mercury globules come together forming a big globule.Conclusion : The above activity concludes that a force of attraction exists between the particles of matter.(b) Simple experiment to show that particles of matter are closely packed in solids and less in liquids:Procedure : 100 ml of water is taken in a measuring cylinder. Crystals of sugar (solid) are added to the water to obtain sugar solution. The volume of water, even after adding sugar remains the same at 100 ml.Conclusion : This concludes that particles of matter are closely packed in solids and less closely packed in liquids. The sugar particles fill the intermolecular spaces which must be existing between the water molecules and hence the level of the water in the measuring cylinder does not rise.

Question 11

Question 12Explain the term 'interconversion of matter' - with ice as a starting material. State the term which refers to the conversion of a substance on heating from -(a) Solid state to liquid state.(b) liquid state to vapour state.(c) vapour state to liquid state.(d) liquid state to solid state.

Accepted Answer

Taking ice as a starting material, 'interconversion of matter' can be understood in the following way:On heating, ice which is in solid state melts and changes into water which is in liquid state.On further heating, water changes into vapour which is in gaseous state.When water vapour is allowed to cool, it changes from gaseous state to liquid state forming water.On cooling water further, it changes to solid state forming ice.Thus, 'interconversion of matter' involves change of state of matter from one state to another and back to its original state by change in temperature or pressure.(a) Melting(b) Vaporisation(c) Liquefaction or Condensation(d) Solidification or freezing

Question 12

Question 13Give a reason why solids and liquids co-exist at their melting points.

Accepted Answer

At melting point, solid start changing into liquid state. Heat is absorbed and it is used in change of state without any rise in temperature till all the solid has changed into liquid state. Hence, the two states i.e., solid and liquid co-exist at melting point.

Question 13

Question 2Select the correct answer from the choice in bracket to complete each sentence:Matter is defined as anything that occupies ............... & has ............... [mass/volume/space].The three states of matter are classified on the basis of differences of certain ............... [chemical/physical] properties.Matter made up of one kind of particles is said to be ............... [heterogeneous/homogeneous]Particles in a gas possess ............... [least/very large] kinetic energy.The intermolecular force of attraction is ............... [negligible/maximum] in solids.

Accepted Answer

Matter is defined as anything that occupies space & has mass.The three states of matter are classified on the basis of differences of certain physical properties.Matter made up of one kind of particles is said to be homogeneous.Particles in a gas possess very large kinetic energy.The intermolecular force of attraction is maximum in solids.

Question 14

Question 5Match the arrangement of atoms in three states of matter in List I with the correct state in List IIList IList II1. Arrangement of atoms, very closely packedA: Solids2. Interparticle space is maximumB: Liquids3. Force of attraction between particles is very weakC: Gases4. Movement of particles is about their own position5. Particles in the state of matter are slightly compressible & not closely packed

Accepted Answer

List IList II1. Arrangement of atoms, very closely packedA: Solids2. Interparticle space is maximumC: Gases3. Force of attraction between particles is very weakC: Gases4. Movement of particles is about their own positionA: Solids5. Particles in the state of matter are slightly compressible & not closely packedB: Liquids

Matter and Its Composition

Exercise

Experimental Study

Objective Type Questions