environmental chemistry - Category wise Question and Answer Practice Test with Solutions

Question : 21

Frequent occurrence of water blooms in a lake indicates

a) oxygen deficiency

b) excessive nutrient availability

c) nutrient deficiency

d) absence of herbivores in the lake

Question : 22

Consider the following statements:

1. Use of fertilizers has role on water pollution
2. Excessive use of pesticides help to decrease water pollution.

a) 2 only

b) 1 only

c) 1 and 2

d) None

Question : 23

Acid rains is caused due to emission of which of the following into the atmosphere?

a) Carbon dioxide and carbon monoxide

b) Oxides of nitrogen and sulphur

c) Ozone and carbon dioxide

d) Carbon monoxide and nitrogen

Question : 24

Biochemical Oxygen Demand, (BOD) is a measure of organic material present in water. BOD value less than 5 ppm indicates a water sample to be __________.

a) poor in dissolved oxygen

b) highly polluted

c) rich in dissolved oxygen

d) not suitable for aquatic life

Question : 25

Phosphate pollution is caused by

a) weathering of phosphate rocks only

b) agriculutral fertilizers only

c) sewage and agricultural fertilizers

d) phosphate rocks and sewage