How do organic substances cause water pollution ? Explain the term C.O.D. and B.O.D.

What are the major causes of water pollution? Explain.

Give the significance of the terms B.O.D. and C.O.D.

[A] : An estimation of B.O.D gives an indication of the amount of pollution in a body of water . [R] : B.O.D is measure of the oxygen requirements of the bacteria , which are living in the water .

Black water fever is caused due to (a) Nitrate pollution in water (b) Infection of Leishrmiania donovani (c) Infection by sporozoan Plasmodium (d) Infection of Yersinia pestis

High biological oxygen demand in a water body means ………. (a) water is not polluted (b) water is less polluted (c) water body contains lots of life forms and organic pollutant. (d) None of the above

How many cases have 'Dipole-induced dipole' interaction ? (a) Br_2 in water , (b) NH_3 in H_2O , (c) CO_2 in water , (d) O_2 in water , (e) 'Xe' in water

A B ,\ C D ,\ a n d\ E F are three concurrent lines passing through the point O such that O F bisects /_B O D. If /_B O F=35^0, find /_B O C and /_A O Ddot

In Figure, find x . Further find /_B O C ,\ /_C O D\ a n d\ /_A O D .

Which of the following is a secondary pollutant ? (A) O3 (B) SO2 (C) CO2 (D) CO

Suppose line segments A B and C D intersect at O in such a way that A O=O D and O B=O C . Prove that A C=B D but A C may not be parallel to B D .