Frank ICSE Solutions for Class 9 Chemistry – Atmospheric Pollution

Frank ICSE Solutions for Class 9 Chemistry – Atmospheric Pollution

PAGE NO :158
Solution 1:
Acid rain is the rain that has an excessive amount of acid in it than that of normal. Two air pollutants that cause acid rain are-

    1. Oxides of nitrogen
  1. Oxides of sulphur

Solution 2:
Acid rain is responsible for retarding forest’s growth and other vegetation. Acid rain makes the soil acidic and adversely affects the plants.

Solution 3:
70% of acid rain is due to sulphur dioxide. Oxides of sulphur and nitrogen released into atmosphere from number of sources.These oxides of nitrogen gets converted into nitrogen dioxide(NO2) which reacts with water to form nitric acid.Similarly, sulphur dioxide reacts with atmospheric oxygen to form sulphur trioxide which with water forms sulphuric acid.These come down on earth as acid rain.

Solution 4:
Acid rain can be reducd by-

  1. There should be reduction in fossil fuel combustion.
  2. Use of alternate cleaner energy sources should be encouraged. Eg-nuclear power, hydro power, wind energy, solar energy etc.
  3. Air filters and scrubbers are fitted in tall industrial chimneys to control air pollution.
  4. Catalytic converters in vehicle reduce nitrogen oxide emissions from automobiles.

Solution 5:

Acid rain cause extensive damage to the environment.

  1. Vegetation – The acid rain makes the soil acidic. This adversely affects the plants and animals. This damages leaves of plants and trees. This is responsible for retarding forests and other vegetation.
  2. Fertility of soil – The activity of symbiotic nitrogen fixing bacteria present in the nodules of leguminous family is inhibited. This is responsible for destroying or reducing the fertility of the soil.
  3. Water bodies – Acid rain renders the river, lakes or even ocean water acidic, there by adversely affecting marine animals. Changes in pH affect the reproduction and survival of many species of fish and other animals.
  4. Buildings and monuments – Acid rain cause extensive damage to the buildings and monuments made from marbles, limestone, slate and mortar.
    Frank ICSE Solutions for Class 9 Chemistry - Atmospheric Pollution 1
  5. Ecological balance – Acid rain is responsible for wiping out many bacterial and blue green algae, so disrupting the whole ecological balance.
  6. Human health – Acid rain has been found to be dangerous to human health. Acidic conditions can affect human nervous, respiratory and digestive systems.

Solution 6:
Air pollution is a harmful change in the natural air quality. It includes all physical, chemical and biological agents that modify the natural characteristics of the atmosphere.

Solution 7:
Ozone is an allotrope of oxygen. It has three oxygen atoms and its molecular formula is O3.It is an unstable blue gas having pungent odour found in troposphere. It is used as a powerful oxidant, bleach and water purifier.

Solution 8:
The gases causing ozone depletion are-

  1. Chlorofluoro carbons(CFCs or freons)
  2. Methane
  3. Nitrous oxides
  4. Carbon tetrachloride
  5. Methyl bromide(a soil fumigant and insecticide)
  6. Aircraft emission
  7. n-propyl bromide and Halon-1202

Solution 9:
Greenhouse gases are-

  1. Water vapour(H2O)
  2. Carbon dioxide(CO2)
  3. Methane(CH4)
  4. Oxides of nitrogen(NOx)

Solution 10:
Frank ICSE Solutions for Class 9 Chemistry - Atmospheric Pollution 2

Solution 11:
Greenhouse effect means the progressive warming up of the earth’s surface due to the blanketing effect of man made carbon dioxide in the atmosphere. Greenhouse is a glasshouse with plants inside and  which allows short wave, incoming solar radiation to come in but does not allow the long wave,i.e. outgoing  infrared radiation to escape from inside the structure. Some of the gases in the earth’s atmosphere act like the glass in a greenhouse.They trap sun’s heat and keep the surface of the earth warm. Carbon dioxide and water vapour act as a greenhouse.

Solution 12:
Global warming is rise in the average global earth temperature . An increase in the average temperature of the earth’s atmosphere due to greenhouse effect  which can have far reaching effects on the climate and consequently on the key life, support systems of the planet, and this phenomenon is called global warming.

Solution 13:
Frank ICSE Solutions for Class 9 Chemistry - Atmospheric Pollution 3f

Solution 14:

  1. The warmer climate is changing the patterns of rainfall and snowfall.
  2. It causes increase in the frequency and severity of drought and flood also.
  3. It  is affecting our resources like water,forests  and different ecological systems.
  4. It also cause frequent natural disasters like cyclones, storms and hurricanes,floods and droughts.
  5. The global warming is damaging various ecosystems like mangrove-swamps , coral reefs and coastal lagoons, etc. due to various reasons like reduction in pH of oceanic water and increasing deposits of acids.
  6. It is damaging the world biodiversity. Vast varieties of birds, reptiles, insects, bacteria, fungi, rodents etc.have vanished out due to these effects.

Solution 15:
It has been found that in every southern spring(September-October) 50-95 %  of stratospheric ozone is destroyed at a height of 15-24 kms above ‘Antarctica’ creating pockets which have been described as ozone hole.

Solution 16:
The adverse effects of ozone layer depletion are-

  1. UV radiation causes sun-eye diseases (cataract), skin diseases, skin cancer and damage to immune system in our body.
  2. It damages plants and causes reduction in crop productivity.
  3. It damages embryos of fish, shrimps, crabs and amphibians.
  4. UV radiation damage fabrics, pipes, paints and other non-living materials on this earth.
  5. It contributes in the global warming. If the ozone depletion continues, the temperature around the world may rise at faster rate and to a large extent.

Solution 17:
Natural greenhouse effect is a process of thermal blanketing of the earth which maintains its temperature to sustain life on it. Without greenhouse effect, the climate of the earth would be too cold for most of the life to survive.

Solution 18:
The effect of warming and insulation of the earth caused due to some heat trapping gases accumulated in the atmosphere after their emission from the earth surface is called as greenhouse effect. Due to this there is rise in the average global earth temperature called global warming.

Solution 19:
When an ozone molecule is hit by UV wavelengths, it absorbs the radiant energy and photo dissociates into O2 and O giving off heat. Thus, keeps the UV radiation from reaching the earth’s surface and also causes a temperature inversion in the stratosphere that helps to maintain relatively stable climatic conditions on and near the ground.

Solution 20:
When an ozone molecule is hit by UV wavelengths, it absorbs the radiant energy and photo dissociates into O2 and O giving off heat. Thus, keeps the UV radiation from reaching the earth’s surface and also causes a temperature inversion in the stratosphere that helps to maintain relatively stable climatic conditions on and near the ground.

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Frank ICSE Solutions for Class 9 Chemistry – Practical Work

Frank ICSE Solutions for Class 9 Chemistry – Practical Work

PAGE NO :170
Solution 1:
On heating certain solids they don’t melt and directly get converted to their gaseous form, this process of direct conversion of solids to their gaseous form is called as sublimation. For ex: camphor and ammonium chloride undergo sublimation.

Solution 2:
Decrepitation is a process of breaking up of solid particles on heating, which makes a crackling sound. Lead nitrate decrepitate on heating.
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 6
Lead nitrate

Solution 3:
(a) Zn(NO)3        = white
(b) Cu(NO3)2      = blue
(c) CuSO4.5H2O  = blue
(d) CuSO4          = pale green
(e) K2Cr2O7       = orange
(f) PbS               = black

Solution 4:
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 1

Solution 5:
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 2

Solution 6:
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 3

Solution 7:
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 4

Solution 8:
(a) Rotten egg
(b) Burning sulphur
(c) Nitrogen dioxide
(d) Alkali
(e) Ca(OH)2
(f) Lilac
(g) Brick-red

Solution 9:
Point sources of water pollution: Sources of water pollution that discharge directly into the water source are called as point sources of water pollution.
For ex: factories
Non point sources of water pollution: sources of water pollution that remain scattered and don’t have specific locations for the discharge of pollutants into particular water bodies are called as non point sources of water pollution.
For ex: run off from fields.

Solution 10:
Frank ICSE Solutions for Class 9 Chemistry - Practical Work 5

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Frank ICSE Class 10 Biology Solutions – Nervous System

Frank ICSE Class 10 Biology Solutions – Nervous System

PAGE NO 115
Solution 1:

  1. Central Nervous System
  2. Autonomic Nervous System
  3. Conus medullaris / Medullary cone
  4. Mixed neurons
  5. Neuroscience
  6. Sensory neurons
  7. Motor neurons
  8. White matter
  9. White matter
  10. Dura mater
  11. Neuron
  12. Meninges
  13. Cranium
  14. Neocortex / Neopallium
  15. Limbic system
  16. Corpora quadrigemina
  17. Olfactory Lobes
  18. Median fissure
  19. Agraphia
  20. Brain
  21. Aphasia
  22. Trigeminal nerve
  23. Sympathetic nervous system
  24. Dendrites
  25. Bipolar neuron
  26. Sclera
  27. Myopia
  28. Semicircular canal
  29. Rhodopsin

PAGE NO : 116
Solution 2:

  1. Ear pinna – The pinna or the external ear collects the sound waves from different directions and send them to the middle ear.
  2. External auditory meatus It forms a passage from the pinna to the eardrum.
  3. Cochlea – It converts vibrations into nerve impulses and thus helps in hearing.
  4. Semicircular canals – It responds to change in position and maintains balance.
  5. Lachrymal gland – It secretes a watery fluid which washes the surface of eyes.
  6. Eyelids – It blinks to clean the dust and grit from the cornea.
  7. Retina – It is a photosensitive layer to receive the image.
  8. Eye lens – It focuses the image on the retina.
  9. Pupil – It regulates the amount of light that enters the eye.
  10. Olfactory lobe – These are concerned with the sense of smell.
  11. Optic lobe – These are concerned with vision.
  12. Medulla oblongata – It controls involuntary functions of the body like – coughing, swallowing, breathing, heartbeat, etc.

Solution 3:

  1. Nephron
  2. Blind spot
  3. Myelin
  4. Olfactory lobe
  5. Cranial nerve

Solution 4:
Frank ICSE Class 10 Biology Solutions - Nervous System 1

Solution 5:

  1. Nerve impulse – It is an electrochemical change occurring in the membrane of a nerve fibre produced by a stimulus.
  2. Axon – It is a fibre like process of the neuron which carries impulses away from the cell body.
  3. Cyton – It is an oval, angular, polygonal or stellate body which contains a large central nucleus.
  4. Action potential – A momentary change in electrical potential on the surface of a cell, or a nerve or muscle cell, that occurs when it is stimulated, resulting in the transmission of an electrical impulse.
  5. Reflex action – It is an immediate and involuntary response to a stimulus.
  6. Yellow spot – It is the region of best vision where more cone cells are present.
  7. Blind spot – It is the region of no image formation because of lack of cone cells.
  8. Power of accommodation – It is the ability of the lens to focus on far and distant objects.

Solution 6:
Frank ICSE Class 10 Biology Solutions - Nervous System 2
Frank ICSE Class 10 Biology Solutions - Nervous System 3

Solution 7:
Frank ICSE Class 10 Biology Solutions - Nervous System 4

PAGE NO : 117
Solution 8:
Frank ICSE Class 10 Biology Solutions - Nervous System 5

Solution 9:
Frank ICSE Class 10 Biology Solutions - Nervous System 6

Solution 10:

  1. A – Cerebrum; B – Cerebellum; C – Medulla oblongata
  2. (A) Cerebrum – It is concerned with intelligence, memory and voluntary activities.
  3. Cerebellum – It is concerned with body equilibrium.
  4. Medulla oblongata It controls all involuntary activities like heart beat, respiration, etc.
    The three protective membranes covering the brain are :

    •  Dura mater
    • Arachnoid mater
    • Pia mater.
  5. Neuron is the basic unit of the brain.

PAGE NO : 118

Solution 11:

  1. Meninges – It is located around the brain and spinal cord.
  2. Ganglia – It is located outside the brain and spinal cord.
  3. Cerebellum – It is located behind cerebrum and above medulla oblongata in the brain.
  4. Nodes of Ranvier – It is located on the unmyelinated areas on the axon.
  5. Effector organs – It is located in muscle , gland or any organ of the body.

Solution 12:
Frank ICSE Class 10 Biology Solutions - Nervous System 7

Solution 13:
Frank ICSE Class 10 Biology Solutions - Nervous System 8

Solution 14:

  1. Iris: It is located in the eye. Its function is to protect the eyeball and controls the size of the pupil.
  2. Semicircular canals: It is located in the inner ear. These are concerned with the body equilibrium.

Solution 15:
Following are the two examples of reflex actions in our daily life :

  1. Removing hand suddenly when pricked by a thorn.
  2. Blinking of eyelids on exposure to light.

Solution 16:

  1. Reflex action – It is an immediate and involuntary response to a stimulus.
  2. Example of a conditioned reflex: Tying one’s shoe lace.

Solution 17:

  1. (a) Bone of skull
  2. (b) Inner ear
  3. (c) Eardrum
  4. (d) Bone of skull
  5. (e) Bone of middle ear
  6. (f) Middle ear
  7. (g) Air filled
  8. (ii) (b) Inner ear – It transmits the impulse to brain.
  9. (d) Bone of skull – It helps in fixing the position of the ears to help the brain use auditory cues to judge direction and distance of sounds.
  10. (g) Air filled – It keeps the pressure in the middle ear equalized with pressure in the outside.
  11. (iii) The main division of the ear are: outer ear, middle ear and inner ear.
  12. (iv) Stirrup
  13. (v) The labyrinth is the inner ear which consists of utriculus, sacculus, cochlea and three semicircular canals.

Solution 18:

  1. A – Semi-circular canal
    B – Utriculus
    C – Sacculus
    D – Cochlea
    (ii) Auditory nerve.
    (iii) 1. Utriculus and sacculus
  2. Semi-circular canal
  3. Cochlea
  4. Sensory cells of organ of Corti
  5. Perilymph

Solution 19:

  1. Cochlea – It helps in hearing by transmitting impulses to the brain through auditory nerves.
  2. Fovea centralis – It is a point at retina where more cone cells are concentrated and thus produces sharpest vision.
  3. Three semicircular canals – It maintains the dynamic equilibrium.
  4. Retina – It prevents the reflection of light.
  5. Lachrymal glands – It produces tear to lubricate the eyeball.

Solution 20:
The arrangement of neurons in
Cerebrum: cytons are present outside and axons are inside
Spinal cord: cytons are present inside and axons are outside.

Solution 211:
Functions of medulla oblongata –

  1. It controls the involuntary activities like – respiration, circulation, digestion, etc.
  2. It controls the dilation and constriction of blood vessels.

Solution 22:
Reflex action – It is an immediate and involuntary response to a stimulus.
Example – 1. Blinking of eyelids on exposure to light .
2. Knee jerk.

PAGE NO : 119

Solution 23:
Frank ICSE Class 10 Biology Solutions - Nervous System 9

Solution 24:
Cone cells.

Solution 25:
Frank ICSE Class 10 Biology Solutions - Nervous System 10

Solution 26:
Frank ICSE Class 10 Biology Solutions - Nervous System 11

Solution 27:

  1. Cochlea: It helps in hearing by transmitting impulses to the brain through auditory nerves.
  2. Meninges: It provides protection to brain and spinal cord.

Solution 28:
One feels blinded for a short while on coming out of a dark room.This is called light adaptation of the eye.It is due to the constriction of the pupil to prevent the entry of light into the eye and pigment rhodopsin is bleached to reduce the sensitivity of the rods.

Solution 29:

  1. Iris
  2. Cerebrospinal fluid

Solution 30:

  1. True
  2. True
  3. True
  4. True
  5. False
  6. True
  7.  False
  8. False

PAGE NO : 120
Solution 31:

  1. (d) nerve cell
  2. (b) cerebrum
  3. (a) 31
  4. (b) 12
  5. (a) dura mater
  6. (a) ear
  7. (c) rhodopsin
  8. (a) twilight vision
  9. (d) macula
  10. (d) two nerves
  11. (c) hearing
  12. (b) 31
  13. (a) eustachian
  14. (c) iris
  15. (b) cones
  16. (b) Ear
  17. (d) corpus callosum
  18. (d) eye
  19. (d) filter light
  20. (b) the two cerebral hemispheres

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Frank ICSE Solutions for Class 9 Chemistry – Matter and its Composition: Law of Conservation of Mass

Frank ICSE Solutions for Class 9 Chemistry – Matter and its Composition: Law of Conservation of Mass

PAGE NO :8
Solution 1:
Matter is anything around us which occupies space and has mass. Example- Coal, Copper, Water, Oxygen, Kerosene
Key: Matter occupies space and has mass.

Solution 2:
The conditions for something to be called matter are –

  1. It should occupy space.
  2. It should have mass.

Solution 3:
Light and sound are not considered to be matter because they neither have mass nor do they occupy space.

PAGE NO :9
Solution 4:
Solid:

  1. The particles are held together by strong intermolecular forces and have minimum intermolecular space.
  2. Solids have definite mass, shape and volume.

Liquid:

  1. The intermolecular forces of liquid molecules are intermediate of molecules  of solids and gases while intermolecular spaces are greater than in solids.
  2. Liquids have definite mass and volume but not definite shape. They take the shape of the container.

Gas:

  1. The particles are held together by very weak intermolecular forces while intermolecular spaces are much greater than in solids.
  2. Gases have definite mass but not definite shape and volume. They take the shape of the container.

Solution 5:
Two reasons for saying that wood is a solid are-

  1. Wood has definite mass and shape.
  2. Their intermolecular forces are very strong so they cannot flow.

Solution 6:
The particles of gases are separated from each other by large spaces and intermolecular forces of attraction are the weakest in gases. They have least density. So, they can flow easily. Hence, gases have no fixed shape and volume.
Key: Intermolecular forces of attraction are the weakest in gases.

Solution 7:

  1. Gases
  2. Solid
  3. Solid

Solution 8:

PropertiesSolidsLiquidsGases
1.State of packingThe particles are closely packed and their positions are also fixed.The particles are loosely packed and their positions are not fixed.The molecules are wide apart and their positions are also not fixed.
2.Energy associatedParticles can vibrate only to and fro about their mean positions. Therefore, they have small kinetic energy due to their motion.The particles can move about more freely and have considerable kinetic energy due to their motion.The particles move about freely and have maximum kinetic energy due to their motion.
3.Intermolecular forcesThe particles are held together by strong intermolecular forces.The particles are held together by weak intermolecular forces.The particles are held together by very weak intermolecular forces.
4.Physical featuresSolid has a crystalline structure with both definite size and definite shape.Liquid does not have a definite shape but has definite volume and can flow from higher to lower level.Gas has neither definite shape nor a definite volume but can flow and is easily compressible.

Solution 9:

  1. gases
  2. strong
  3. sublimation
  4. Condensation
  5. gaseous

Solution 10:
The postulates of the kinetic theory of matter-

  1. Composition of Matter: Matter, whether in the solid, liquid or gaseous state, is composed of very small particles which may be molecules, atoms or ions.
  2. Arrangement of Particles: These particles have spaces lying between them and these spaces are referred to as intermolecular spaces or interparticle spaces.
  3. Forces of Attraction: The forces of attraction between the molecules of a given substance are called intermolecular forces. The magnitude of this force depends upon the state of the substance and on the magnitude of the intermolecular spaces. As the intermolecular space increases, the intermolecular force decreases.
  4. Motion of the constituent particles: The particles are always in a state of motion. In solids, they vibrate about their mean positions and in liquids and gases, they move randomly.
  5. The kinetic energy of the particles increases with rise in temperature. As the temperature is increased, the particles undergo motion more vigorously and more  randomly.

Solution 11:

  1. Solid to liquid state: The conversion of a substance from the solid state to liquid state at a particular temperature is called melting or fusion. The heat energy supplied to the solid is absorbed by its molecules to gain kinetic energy. The kinetic energy increases the rate of vibration of the molecules. The force of attraction thus no longer holds the molecules close together and the solid gets change into liquid.
  2. Gas to liquid: The conversion of a substance from the gaseous state to its liquid state at a particular temperature is called condensation or liquefaction. On cooling, the gas molecules loose their kinetic energy in the form of lost heat and so molecular motion slows down. Decreased molecular motion causes a decrease in intermolecular space. The molecules come very close and the force of attraction between them correspondingly increases and the gas gets change into liquid.
  3. Liquid to gaseous state: The heat energy supplied to the liquid is absorbed by its molecules to gain kinetic energy and therefore the molecules move faster. This increases the intermolecular space. The intermolecular force of attraction decreases and liquid changes into gaseous state.
  4. Liquid to solid state: The conversion of a substance from the liquid state to solid state by cooling is called freezing. On cooling a liquid, the kinetic energy of the molecule is decreased. Due to decreased kinetic energy, the molecules cool down and come closer, thus reducing the intermolecular spaces. The force of attraction between the molecules thus increases. Now, the molecules are no longer in a position to be free or to migrate and liquid changes into a solid.

Solution 12:

  1. Freezing: The process of changing a liquid into a solid by cooling is called        freezing. Freezing means solidification. It occurs at a definite temperature called freezing point.
  2. Evaporation: The phenomenon involving the change of a substance from the liquid state to the gaseous state at room temperature or at any other temperature below its boiling point is called vaporization or evaporation.
  3. Boiling point: The temperature at which a liquid boils and changes rapidly into a gas at atmospheric pressure is called boiling point of the liquid.
  4. Melting point: The temperature at which a solid substance changes into its liquid state at 1 atmospheric pressure is called the melting point of that substance.

Solution 13:

  1. Size of naphthalene balls decreases – Sublimation
  2. Drying of wet clothes – Evaporation
  3. Wax melts in the sun – Melting
  4. Formation of clouds – Evaporation and Condensation

Solution 14:
Three compounds which are sublimate are-

  1. Camphor
  2. Naphthalene
  3. Iodine

Solution 15:
‘States of matter triangle’ shows inter-conversion of states of matters.
Frank ICSE Solutions for Class 9 Chemistry - Matter and its Composition Law of Conservation of Mass 1

Solution 16:
The process by which a liquid slowly converts into vapour state at a temperature below its boiling point is called evaporation.
The heat energy is absorbed by the liquid to convert it into vapour state. So, loss of heat causes cooling.

Solution 17:

  1. True
  2. True
  3. False
  4. True

Solution 18:
“In all physical and chemical changes, the total mass of the reactants is equal to that of the products”. So, in other words matter can neither be created nor destroyed.

Solution 19:
Frank ICSE Solutions for Class 9 Chemistry - Matter and its Composition Law of Conservation of Mass 2

Solution 20:

  1. Matter
  2. Solid
  3. Gas
  4. Solid
  5. Gas
  6. Gas
  7. Liquid
  8. Fluid
  9. Melting
  10. Vaporization

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Frank ICSE Solutions for Class 9 Chemistry – Study of Gas Laws

Frank ICSE Solutions for Class 9 Chemistry – Study of Gas Laws

PAGE NO :21
Solution 1:
An ideal gas can be characterized by three state variables:

  1. Absolute pressure (P),
  2. Volume (V), and
  3. Absolute temperature (T).

Solution 2:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 1

Solution 3:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 2

Solution 4:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 19

Solution 5:
Kelvin zero is – 273.15 oC.

Solution 6:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 3

Solution 7:
The standard temperature and pressure (STP) by general convention are 0 oC(273 K) and 1 atm(760 mm Hg).

Solution 8:

  1. The value of standard temperature is (i) 0 oC and (ii) 273 K
  2. The value of standard pressure is (i) 1 atm, (ii) 760 mm of Hg, (iii)76 cm of Hg, (iv)760 torr

Solution 9:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 4

Solution 10:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 5
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 6

Solution 11:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 7

Solution 12:
There is simultaneous effect of temperature and pressure changes on the volume of a given mass of a gas. So, when stating the volume of a gas, the pressure and temperature should also be given.

PAGE NO :22
Solution 13:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 8

Solution 14:

  1. Volume of a gas would be reduced to zero at 0 K (-273 0C).All temperatures on the Kelvin scale are positive, so Kelvin scale has been adopted for chemical calculation.
  2. At absolute zero temperature, volume of a gas would be reduced to zero. Theoretically,this is the lowest temperature that can be reached. At this temperature all molecular motions cease. Thus, practically this temperature is impossible to attain because on cooling gases liquefy and Charles’ law is no more applicable.
  3. According to combined gas law equation, there is simultaneous effect of temperature and pressure changes on the volume of a given mass of a gas. So, when stating the volume of a gas, the pressure and temperature should also be given.

Solution 15:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 9

Solution 16:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 10

Solution 17:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 11

Solution 18:

  1. True
  2. False
  3. False
  4. False
  5. False

Solution 19:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 12

Solution 20:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 13

Solution 21:
We trap a definite quantity of  air in the closed vessel. At any point, the pressure on the air is equal to the atmospheric pressure plus the pressure due to the excess mercury column in the open end tube. By pouring mercury in the tube, we increase the pressure on the air and measure its volume under that pressure. We thus obtain a set of data for the volume of a fixed mass of air under different pressures.
For a given mass of air at constant temperature, the following observations are made-

  1. The volume of air decreases with increasing pressure and vice versa.
  2. The proportion by which the volume decreases or increases is the same by which the pressure increases or decreases.

Solution 22:

  1. Pressure will also be doubled.
  2. Pressure will be double.

Solution 23:

  1. 273
  2. absolute zero
  3. absolute temperature
  4. the average kinetic energy

Solution 24:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 14

Solution 25:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 15

Solution 26:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 16

Solution 27:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 17

Solution 28:
As weather balloon go higher into the atmosphere, the air becomes less dense, so air pressure drops. Because of this, the air that is already inside the balloon  expands to cope with the difference in pressure. The end result is that the balloon expands making it larger.

Solution 29:
Frank ICSE Solutions for Class 9 Chemistry - Study of Gas Laws 18

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