Give two examples of suitable alternatives of CFCs which can be used as refrigerant and are non-ozone depleting?

(a) Name the common refrigerent. How does it deplete ozone layer ?

(b) What is the alternative of chlorofluoro carbon ?

(c) State the advantages and disadvantages of using ammonia as refrigerent ?

Q Which of the following are Ozone Depleting Substances (ODS)?

Select the correct answer using the code given below.

1. 
   1 and 3 only
2. 
   1, 2, 3 and 4 only
3. 
   1, 2, and 4only
4. 
   2 and 4 only

Which pollutant released into the air during refrigeration and airconditioning is the greatest contributor to the depletion of ozone layer ?

(a) BHC (b) DDT (c) CFC (d) UNEP