58) The disinfection efficiency of chlorine increases by i) decreasing the time of contact ii) decreasing the temperature of water iii) increasing the temperature of water The correct answer is

59) Chlorine demand of water is equal to

60) The process in which the chlorination is done beyond the break point is known as

61) The percentage of chlorine in fresh bleaching powder is about

62) The treatment of water with bleaching powder is known as