Tag: chemistry
Questions Related to chemistry
Pollution of lakes and rivers affects aquatic life. Fish cannot live in water that has oxygen less than $4$ milligrams per liter. Other freshwater aquatic life (including anaerobic bacteria) also cannot survive without adequate oxygen. 'BOD' stands for:
Clean water would have Biochemical oxygen demand (BOD) value of less than:
Biological Oxygen Demand (BOD) can be defined as:
What does $BO{D} _{5}$ represent?
10 mL of water required 1.47 mg of $K _{2}Cr _{2}O _{7}$ (M. wt. = 294) for oxidation of dissolved organic matter in presence of acid. Then the C.O.D of water sample is:
Salt, sugar, and many other substances dissolve in water to form :
Two main constituents of air are :
Which of the following is a homogeneous solution?
Air is a ______ mixture.
Aqueous solutions of low molecular mass solutes are :