sea water an a. Water vapour 3. The conversion of the vapour of a substance to its liquid form happens by the process of fresh water a. condensation b. evaporation C. transpiration d. precipitation 4. Abnormally long period of insufficient or no rainfall is a. flood b. epidemic c. famine d. drought 5. What are the tiny ice crystals of water droplets floating in the air called? b. Clouds C. Precipitation d. Water cycle 6. Which of the following is not the result of a drought? a. Rivers run dry b. Lack of food c. Water logging d. Thirst and dehydration 7. Which of the following is an outcome of a flood? a. Water-borne diseases b. No rainfall C. Fresh water d. Drought 8. The plants give off water vapour through their leaves by the process of a. condensation b. evaporation c. transpiration d. precipitation 9. Which of the following is not a method of conservation of water? a. Avoiding wastage of water b. Building dams C. Rainwater harvesting d. Pollution of water 10. Which of the following will lead to wastage of water? a. Shower bath b. Repair of leaky pipes and taps C. Watering plants in the morning d. Using a wet cloth to clean the car
Answers
Answer: 1. Natural sources of salty water Sea Oceans
2. Industrial usage of water Cleaning Cooling
3. Ways of saving water Avoiding wastage Rainwater harvesting
4. Pollutants of water Garbage Harmful chemicals
Answer:
three states—solid, liquid and gas.Liquid state: The water that we use in everyday life is a liquid. It is called liquid state of water.Gaseous state: We have learnt that on heating, water evaporates to form its vapour. Water vapour is its gaseous state.Solid state: Water turns into ice on cooling. Ice is the solid form of water.These three states of water are interconvertible to each other, that is, we can change it from one state to another.
The easy interconvertibility of water from one state to other makes its availability in all parts of the earth and throughout the year.
Evaporation
The process of changing water to its vapour form is known as evaporation.Evaporation takes place from open surfaces of water all the time—day and night.Evaporation of water takes place continuously from oceans, rivers, lakes, wells and soil. Oceans, seas, rivers, lakes, ponds and wells together are often known as water bodies.During the day time, sunlight falls on the water in oceans, rivers, lakes. The fields, roads, rooftops and other land areas also receive sunlight. The sunlight also carries heat with it. As a result, water from oceans, rivers, lakes and the soil, and other land areas gets continuously changed into vapour.Thus, water vapour gets continuously added to air due to evaporation.
Transpiration
Transpiration: It is the loss of water from the leaves of plants in the form of vapour.Every plant, whether it is in a crop field, a forest, on the roadside or in a kitchen garden, transpires to give off water vapour. The amount of water vapour that goes into air through the process of transpiration is very huge.
Condensation
Condensation: The process of conversion of vapour into liquid form of water is called condensation.The process of condensation is opposite to evaporation.Cloud formation: The climate close to the earth’s surface is warm. It gets cooled as one goes up in atmosphere. Water vapour being lighter, rises up in the atmosphere. At the upper layer of atmosphere, where the temperature is lower, the vapour gets condensed into tiny water droplets and forms clouds.
Precipitation
Precipitation: Clouds carry small droplets of water in