Test: Chemical Characteristics of Waste Water - Civil Engineering (CE) MCQ

At least, 4ppm of dissolved oxygen should be present in treating sewage otherwise, fishes will die due to lack of dissolved oxygen.

The temperature and dissolved oxygen are inversely proportional to each other.

The presence of free ammonia in sewage represents recent pollution. Which can be removed from wastewater by the nitrification process.

The presence of Albuminoid nitrogen in water indicates the decomposition of sewage has not taken place.It nitrogen is also called as organic nitrogen.

The suspended solids float in sewage. 1000kg of sewage contain 0.112 kg of suspended solids.

Potassium chromate is used for the titration of waste water with silver nitrate solution for finding the chloride content.

Wrinkler method is used to find the D.O content of sewage where the D.O content is proportional to the titration of iodine with S₂O₃^2- solution.

The presence of nitrates indicates the old pollution. It also means that the nitrogen is fully oxidized in sewage.

Imhoff cone is used to measure the settleable solids where wastewater is allowed to stand for a specific time, solids get settled down and the readings are taken through the graduations on the cone.

Domestic sewage includes waste from kitchen, laundry, toilet, bathroom, etc., which contain higher amount of chloride content, so the permissible dose of 120ppm is kept for domestic sewage.