Engineering Questions with Answers - Multiple Choice Questions
Environmental Engineering MCQ – Physical Characteristics of Waste Water
Which of the following represents the physical characteristics of water?
a) Chloride content
Explanation: Turbidity represents the physical characteristic of water, whereas BOD, COD and chloride content represents the chemical characteristic of water.
Which of the following is measured in mg/L?
a) Unit weight
b) Coefficient of cohesion
Explanation: The turbidity of waste water is measured in mg/L. The other units of turbidity are ppm, NTU and JTU.
Which of the following instrument is used to measure turbidity?
b) Turbidity meter
Explanation: Turbidity can be measured by Jackson’s turbidity meter, Baylis turbidity meter, turbidity rod and Nephelometer.
When the sewage becomes stronger, the turbidity of wastewater?
c) Becomes constant
d) Slightly decrease
Explanation: When the sewage becomes stronger, the milkiness in water increases and thus, the turbidity increases.
Which color indicates the fresh sewage?
Explanation: If the color of sewage is grey, yellow and light brown, then it means that the sewage is fresh.
The color of the septic sewage is __________
Explanation: The color of septic sewage is black or dark brown. It contains either little or no oxygen.
The odor in wastewater is measured by __________
d) Turbidity meter
Explanation: The odor in waste water is measured by Osmoscope which consist of two 10mm diameter glass tubes which is 300mm long and 8mm wide.
In India, the average temperature of sewage is __________
Explanation: The average temperature of sewage is 20oC. The temperature of sewage is higher than that of the water supply.
Identify the incorrect statement from the following?
a) High odor intensity indicates odorless water
b) Fresh sewage is odorless
c) Turbidity can be measured by turbidity rod
d) NTU is a unit of turbidity
Explanation: If the odor intensity of water is 6, it indicates extremely strong odor and when it is 0, it indicates the odorless water.
_______ indicates the freshness of sewage.
Explanation: The color indicates the freshness of sewage. It can be detected easily by the naked eye.
______ represents the number of dilutions required to reduce odor.
b) Threshold odor number
Explanation: The threshold odor number is equal to the volume of samples of water required to add to 100 units of odorless fresh water at which the mixture gives the first detectable odor.
The odor quality of Amines is __________
a) Rotten egg
c) Fecal matter
d) Decayed cabbage
Explanation: The odor quality of Amines is fishy and its chemical formula is CH3NH2.
The odor quality of compound is ammoniacal. Identify the type of compound from the following options.
a) Acetic acid
Explanation: Ammonia has an ammoniacal type of odor quality and its chemical formula is NH3.
The wastewater from the kitchen is an example of __________
a) Black water
b) Yellow water
c) Green water
d) Grey water
Explanation: The wastewater from the kitchen is an example of grey water. It also includes water from the bathroom without urine and feces.
The type of wastewater from the flushing operation of toilet is __________
a) Green water
b) Red water
c) Black water
d) Brown water
Explanation: The type of wastewater from the flushing operation of toilet is black in color and if it does not include urine, then it is brown in color.