SOLUTION

Chlorination is the method which employs the use of chlorine tablets to purify water.

SOLUTION

SOLUTION

These can be removed by boiling the water.

SOLUTION

filtration

SOLUTION

SOLUTION

It is a water treatment process used to settle out the suspended solid particles in water.

SOLUTION

a.   sedimentation

b.   decantation

c.   filtration

SOLUTION

Add chlorine tablets or chlorine drops in water.

After that let it stay for 30 minutes .A slight smell or taste of chlorine indicates that water is safe for drinking.

SOLUTION

1.   Store water in clean containers.

2.   Cover the containers to avoid dust,flies etc,from settling on the water.

3.   Always use a scoop to take out water from big containers.

4.   Never store water in leaking containers.

SOLUTION

1. Funnel

2. filter paper

3. solid residue

4. filtrate

SOLUTION

.

SOLUTION

1)   Plant trees and grass so that they can trap all rain water.

2)   Place mulch around the plants to reduce evaporation and discourage weeds.

3)   Use pool cover to cut down on water evaporation.

4)   Use bucket instead of hose to wash car.

5)   Adjust sprinklers so that they don’t water the sidewalk or streets.

SOLUTION

1)   Check faucet, pipes and toilets for leaks.

2)   Install water shower heads and ultra low flush toilets.

3)   Take short showers during bathing.

4)   Turn off the water while brushing teeth.

5)   Defrost food in the refrigerator.

6)   Rinse vegetables in full sink or pan of water.

SOLUTION

Oxygen

SOLUTION

Nitrogen, oxygen, carbon dioxide, water vapour, hydrogen and helium

SOLUTION

The elements of weather are:

a)Temperature

b)Rainfall

c)Sunshine

d)Wind-speed

e)Amount of cloud cover

f)   Atmospheric pressure

g)Humidity

SOLUTION

When we talk about weather, we are looking at the average of elements like rainfall, temperature, humidity etc, over a short period in a particular place.

SOLUTION

SOLUTION

The atmosphere has five layers:

a)Troposphere

b)Stratosphere

c)Mesosphere

d)Thermosphere

e)Exosphere

SOLUTION

Without the atmosphere, we would be burned by the intense heat of the Sun during the day or frozen by the very low temperatures at night. Due to atmosphere, we experience different types of weather.

SOLUTION

Earth's atmosphere is a critical system for life on our planet. Together with the oceans, the atmosphere shapes the Earth's weather and climate and makes some regions more habitable than others.

SOLUTION

Adverse effects of global warming are:

•      The planet is warming, from North Pole to South Pole. Globally, the mercury is already up by nearly 1 degree Celsius and even more, in sensitive polar regions.

•      Ice is melting at the polar ice caps and mountain glaciers.

•      Sea levels are rising over the last century.

•      Some butterflies, foxes, and alpine plants have moved farther north or to higher, cooler areas.

•      Hurricanes and other storms are  becoming stronger

SOLUTION

Ozone layers absorb the harmful ultraviolet rays of the Sun. However, today due to large amount of pollutants in the atmosphere, this layer is getting depleted.

SOLUTION

Weather

SOLUTION

The amount of cloud cover varies and depends on the rate of evaporation. In places where the Sun’s rays are vertical, and there are large water bodies, rate of evaporation is more, so cloud cover is more.

SOLUTION

SOLUTION

The presence of water vapour in the air is known as humidity. Humidity in the air varies from place to place. Places near the sea are more humid.

SOLUTION

Sun is most important factor affecting rainfall. The rays of the Sun evaporate the water from the sea, rivers and lakes. As the water vapour rises up, it cools and the vapour condenses into droplets of water. These droplets of water form clouds. When a cloud can no longer hold all the water droplets then precipitation occurs in the form of rain or snow.

SOLUTION

(i)

(ii) Prevailing Winds are permanent winds which blow in the same direction throughout the year.

               (iii) As the altitude increases, the temperature decreases. Due to this, the mountain peaks are covered with snow all year round.

SOLUTION

(i)        Prevailing wind

(ii)       Ocean current

(iii)      Warm ocean current

(iv)      Equator

(v)       Trees

(vi)      Industrial revolution

(vii)     Sea breeze

SOLUTION

Columbia and Somalia

SOLUTION

30 years

SOLUTION

WMO

SOLUTION

sponge, dough

SOLUTION

It is a sponge.

SOLUTION

It is the process of condensation.

SOLUTION

It is the liquid state of matter.

SOLUTION

Liquids are also called fluids because liquids can flow from one place to another.

SOLUTION

The liquid obtained when a solute is dissolved in a solvent is called a solution.

SOLUTION

The liquid in which the solute dissolves is called solvent.

SOLUTION

The solid that dissolves in a liquid is called solute.

SOLUTION

If water (liquid) is cooled, it changes to ice (solid). This change is called freezing.

SOLUTION

When gas cools, it changes into liquid state. This process is called condensation.

SOLUTION

If you continue to heat the liquid, it will change into vapour. This process is called evaporation.

SOLUTION

If you heat a solid, it will melt into a liquid. This process is called melting.

SOLUTION

LPG (Liquefied Petroleum Gas) and CNG (Compressed Natural Gas) are compressed in cylinders and are used as fuels.

SOLUTION

Air is mixture of gases like oxygen, nitrogen, carbon dioxide and other gases. Air is always around us.

SOLUTION

Air and cooking gas are the examples of gases.

SOLUTION

Gases can flow easily and take up all the available space. Air is a mixture of gases.

SOLUTION

Liquids can flow. Water, Milk, juices are some common examples of liquids.

SOLUTION

Solids are usually hard. Wood, sand, pencil etc. are some examples of solid.

SOLUTION

Solid, liquid and gas are the three states of matter.

SOLUTION

Anything that has weight and occupies space is called matter.

SOLUTION

(i) cross (iii) ready (iv) school (v) helmet (vi) right (vii) Look (viii) road

SOLUTION

(probable answer)

SOLUTION

This is a regulatory sign. This sign alerts the driver from upcoming turn on the road. It is important that one should know about the upcoming hurdle or alteration of road to prevent accidents.

SOLUTION

Some informatory signs that we see on the road are:

1. Public telephone
2. Hospital
3. First aid
4. Petrol pump
5. Eating places

SOLUTION

We should always cross the road from where you can see the traffic coming from both ways.

SOLUTION

First aid is the immediate medical facility given to an injured person before the doctor arrives.

SOLUTION

One should use a life jacket when you want to learn swimming.

SOLUTION

Always  keep a check on the geysers, electrical switches and other electrical appliances in the bathroom. Never touch them with wet hands. 

SOLUTION

Do not wear synthetic clothes as synthetic clothes catch fire easily. Cotton clothes are best suited for kitchens.

SOLUTION

If an oil catches fire, do not use water to stop it because the burning oil floats on water and can spread all over the place, causing more fire. Instead, put a thick cloth or dry sand over the burning oil.

SOLUTION

Eye injury may be caused by entry of an unwanted object such as dust, small insect cut or by a blow.

SOLUTION

No, we should not crowd around the person. Instead we should let the fresh air come in.

SOLUTION

In case of deeper cuts, we keep the injured part raised so as to stop the flow of blood.

SOLUTION

We wash hands thoroughly before giving first aid because hands are carriers of germs and the wound can get infected.

SOLUTION

vinegar

SOLUTION

synthetic pads

SOLUTION

Agree

SOLUTION

Whenever you participate in sports you can avoid injuries by first warming up, following all rules of the game and wearing proper gear, like helmet, goggles, shoes, pads etc.

SOLUTION

Whenever any person has a sprain or strain you must remember RICE. This stands for rest, ice, compression and elevation.

SOLUTION

First aid is an emergency treatment given to an injured person before one can reach a doctor for help. First aid can reduce the effect of many injuries.

SOLUTION

If you heat a liquid, you will see bubbles on the surface of the liquid. This process is called boiling.

It involves rapid evaporation.

SOLUTION

The states of matter are generally inter-changeable.

Water (liquid) when heated becomes steam, which is a gas and on cooling, water becomes ice (solid).

Similarly, when ice is heated it becomes liquid and water vapours will become water on cooling.

SOLUTION

Two characteristics are:

Gases are substances in which the particles are very loosely packed.

They have no fixed shape. They occupy all the available space in a container.

SOLUTION

Two characteristics are:

1. Liquid are substances in which particles are not very closely packed.
2. Liquids do not have a fixed shape. They take the shape of the container they are poured in.

SOLUTION

Two characteristics are:

1. The particles in solids are closely packed and the space between the particles is very small.
2. Solids are usually hard and have a fixed shape.

SOLUTION

The atmospheric pressure of a place varies with the altitude of the place. Places at high altitude have less atmospheric pressure.

SOLUTION

The Sun affects the weather of a place as it heats the earth unevenly. This uneven heating occurs because the earth’s axis is tilted and the two hemispheres receive uneven amount of sunlight at different times of the year.

SOLUTION

Atmosphere

SOLUTION

Air is tasteless and odourless.

SOLUTION

The continuous movement of air from hot to cold region and vice versa is known as air currents.

SOLUTION

SOLUTION

The above experiment proves that air is required for burning.

SOLUTION

The candle will blow out as the glass will cut out the air supply.

SOLUTION

Compressed air is filled in the tyres.

SOLUTION

Tyres and air pillows

SOLUTION

The polythene bag will become inflated proving that air occupies space.

SOLUTION

Inflated football will weigh more because air has weight.

SOLUTION

The properties are:

a.         Air has weight

b.         Air occupies space

c.          Air can be compressed

d.         Air aids in burning

e.         Air is odourless and tasteless

SOLUTION

Rainfall

SOLUTION

The oxygen that we breathe in helps to produce energy.

SOLUTION

Yes, there is a difference between daytime driving and nighttime driving. One of the most important differences between daytime and nighttime driving conditions is the way in which we see our surroundings. We become completely dependent upon artificial sources of light to show us where we are during nighttime. So, it becomes important to be more careful while driving during nighttime, as we are also much more sensitive to bright lights and other distractions on the road ahead.

For the safety of the pedestrians, one should wear fluorescent clothing when crossing roads at night.

SOLUTION

Very often the cause of accidents is the carelessness on the road. People should follow traffic rules to avoid accidents. Road safety is a matter of education in which the school can play a significant role. Through social education classes, children can be taught the importance of observing the rules of the road. The pedestrians should follow the safety rules by walking on the pavements, follow traffic signals, crossing the road only at zebra crossings to avoid accidents. Motorists should first qualify themselves by learning driving and obtaining the proper licenses. The rash, negligent, drunken driving should be avoided.

SOLUTION

If people will stop following traffic rules on the road, the following things might happen:

1. Nasty traffic jams
2. People will get trapped in a traffic jam, especially the emergency vehicles like ambulances and fire bridge van.
3. It would be nearly impossible to reach anywhere.
4. More accidents will take place
5. People can panic and which could result in quarrels.

SOLUTION

There are certain ways by which we can spread awareness

1. Making posters
2. Starting road safety campaigns
3. Publishing safety articles in newspapers and magazines
4. By emphasizing the importance of road safety through cinemas, TV and radios.
5. With the help of police to instruct drivers about the traffic rules.

SOLUTION

1. Stop just behind the pavement
2. Stop, look, listen to the traffic on the road
3. Look for the zebra crossing or the pedestrian crossing sign
4. Cross the road from the zebra crossing

SOLUTION

answer may vary

SOLUTION

Some safety tips that one should follow while working in the kitchen.

1. Be careful while lighting a matchstick and throw the matchstick only after putting it off. Make sure to throw it away from any item which can catch fire easily.
2. Never play with knives or scissors. Slight carelessness can result in cuts and wounds.
3. If an injury is inflicted, immediately wash it with antiseptic, apply direct pressure to stop bleeding and put a bandage on it.
4. One needs to be extremely careful while being around a stove or handling anything that can light a fire.