Question: Describe the different ways by which water can be purified.
Answer: The different ways by which water can be purified are:
- Sedimentation and decantation
Chlorination: In this method chlorine is added to kill the germs in water. Chlorine tablets are also available in the market which can be used for this process.
Purification Of Water
- Large impurities are removed by sedimentation and decantation. Alum is added to increase the rate of sedimentation (loading).
- Finer impurities are removed by filtration.
- Chlorine is added to kill germs (chlorination).
- Water is stored in big storage tanks to supply to users.
- Clean water is supplied to users.
Question: Describe the layers of atmosphere.
Answer: The different layers of atmosphere are:
- This is the first layer of atmosphere.
- The weather phenomenon like rain, cloud formation and wind happens in this layer.
- Living things can survive in this layer.
- This is the second layer of atmosphere.
- Ozone layer is present in stratosphere which protect us from harmful UV rays radiations that can cause health problems like skin cancer
- Many jet airplains fly in this layer.
- This is the third layer of atmosphere.
- It protect us from meteroids by burning them before they can reach the surface of the earth.
- It is the fourth layer of atmosphere.
- Space shuttles can revolve in this layer.
- It is the last layer of atmosphere.