Variant 5

Variant 5

Test 1. Efficiency of drinking water desinfection by UV-irradiation depends on:

A.doze of radiation; B. time of irradiation;

C.the initial contents of bacteria in water; D. turbidity of water; E. color of water;

Test 2. What is the purpose double chloranation of water using:

A. High initial microbic pollution of water;

B. High colour of water;

C. Impossibility using necessary time of water contact with chlorine;

D. Prevention of high rigidity formation

E. Prevention of galloid-contenting compositions’ formation

Test 3. What should be total microbe number of drinking water?

A.400 B.200 C.300 D.100 E. 500

Test 4. There are following sources of water supply:

A. underground waters B. subsoil waters C. interlayer waters

D. atmospheric waters E. distillation seawater

Test 5. The main parameters of inter- layer waters:

A. practically sterile B. high mineralization C. high pollution

D. high total microbe number E. low mineralization

Test 6. The main parameters of surface waters:

A. practically sterile B. high mineralization C. high pollution

D. high total microbe number E. low mineralization

Test 7. Chemical methods of disinfection of water:

A. Double chlorination B. Boiling C. Ozonization

D. Ultraviolet irradiation E. Ordinary chlorination

Test 8. When double chlorination of drinking water is used?

A. Subsoil water B. Underground inter–layer water

C. Artesian water D. Very dirty water E.Water contain of phenols

Test9. After desinfection of drinking water with chlorine-contenting substances organoleptic properties of water:

A. are improved; B. don’t be changed C.become clear

D. become dark E. are worsened;

Test 10. After desinfection of drinking water with ozone organoleptic properties of water:

A. are worsened; B. are improved; C. don’t be changed

D.become yellow E. become dark