PSC- Elementary Science: Note of Chapter Three-Part 2
In part 2, you get the short answered questions of text and more fill in the blanks and short answered questions. You can see a star sign before some fill in the blanks and short answered questions. These seem to me more important than the others.
Water for life
Short Answered Questions of text
1. Why does water wet the outside of a glass when ice is kept in it?
Ans: Water wets the outside of a glass when ice is kept in it. This water has not come from the ice inside the glass pot. The glass became cold due to the cold ice. Reaching cold surface water vapors of the air turned into water drops.
2. What is the cause of Arsenic pollution?
Ans: There is mineral of Arsenic down in the earth. When Arsenic comes in touch with the layer of water it mixes with the water and pollutes it.
3. What are the diseases caused by drinking polluted water?
Ans: The diseases caused by drinking polluted water are: cholera, dysentery, typhoid and diarrhea, stomach and skin diseases. Drinking of Arsenic polluted water for a long time causes a kind of disease or scar in the hands and legs called Arsenicosis.
Fill in the blanks
1. Water is essential for life.
*2. Plants get water and nutrition from soil.
*3. Water is used as a medium for digestion.
*4. We get our foods from fruits, leaves and grains of plants.
*5. Water is also essential to maintain the proper temperature of our body.
*6. Air contains some vapors all the time.
*7. The tube wells which have Arsenic in water are marked red.
8. We need to drink and use safe water for a healthy living.
*9. When water starts boiling it is to be heated more for twenty minutes to kill the germs in it.
Short answered questions
1. What is hail?
Ans: When water particles in the cloud become extremely cold, the particles turn into ice and falls down on earth as hails.
*2. What is polluted water?
Ans: The water which has any harmful substance mixed in it is called polluted water.
*3. Is there any cure for Arsenicosis?
Ans: There is no easy cure for Arsenicosis. But the cure is possible if the disease is diagnosed during the primary stage and drinking of Arsenic polluted water is stopped.
*4. Is Arsenicosis infectious?
Ans: No, Arsenicosis is not infectious. If one goes to a patient of Arsenicosis there is no possibility of attack by the disease.
5. What should we do during floods and tidal bores?
Ans: It is not possible to boil water during floods and tidal bores. In such a situation water may be purified by mixing it with alum, bleaching powder, halogen tablets etc. in right proportion.
6. How river water is purified and supplied to the houses in big cities?
Ans: River water is purified and supplied to the houses in big cities by mixing it with alum, bleaching power, halogen tablet etc.
Click Below Link for Part1
PSC- Elementary Science: Note of Chapter Three-Part 1