Environmental Studies · Chemistry

Water and Wastewater Treatment

1,345 Questions

This topic deals with water purification, wastewater treatment methods, and industrial effluent management. It includes questions on filtration, disinfection, and water hardness removal. These concepts are tested in environmental science and engineering exams.

Water purificationWastewater treatmentBioremediation strategiesWater hardness removalIndustrial effluent management

Water and Wastewater Treatment Questions

Multiple choice biology environmental pollution control of water pollution protecting our environment rules are for everyone

Which one of the following is not used for disinfection of drinking water?

  1. Chlorine

  2. Ozone

  3. Chloramine

  4. Phenyl
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

Disinfectants are the antimicrobial agents which is mainly used to stop the growth of pathogen on the non-living organism. It may affect the substances on which it is applied. Phenyl is a disinfectant which cannot be used for purification of drinking water because it will kill the pathogens of the bacteria but the quality of the water will  degrade as it is poisonous for the living organisms. It has a pungent odour. All the other options are used as disinfectant because they do not have an adverse effect on the quality of water.

So, the correct answer is option D.

Multiple choice biology environmental pollution control of water pollution protecting our environment rules are for everyone

Treatment of waste water is done by the :

  1. Autotraphic microbes

  2. Heterotrophic microbes

  3. Chemoautotrophic microbes

  4. All of the above
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Autotrophs of greatest significance in sanitary engineering are the nitrifying, sulfur, and iron. Because these bacteria use CO$ _2$ as the carbon source and oxidize inorganic compounds for energy. 

So the correct option is ' heterotrophic microbes'.

Multiple choice biology environmental pollution control of water pollution protecting our environment rules are for everyone

FOAM and the biologists from humboldt state university, california created an integrated waste water treatment, they use plants for purify mainly :-

  1. Sludge from water

  2. Nitrate and phosphate from water

  3. Heavy metals from water

  4. All of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The main purpose of FOAM is to treat wastewater around a place called Arcata and the surrounding bay through a natural system.

So, the correct option is 'Sludge from water'.

Multiple choice biology wastewater story sewage treatment wastewater treatment - need and methods conservation

Which of the following can kill water purifying microbes?

  1. Paints

  2. Cooking oils

  3. Vegetable peels

  4. None of the above
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation
  • The chemical present in paints, Solvents, Insecticides, motor oils, medicines may kill microbes that help purify water. So do not throw them down the drain.
  • Hence Paints can kill water purifying microbes.
  • So, the correct answer is 'Paints'.
Multiple choice biology wastewater story sewage treatment wastewater treatment - need and methods conservation

Use of _______ helps in water purification.

  1. Sodium

  2. Alum

  3. Chlorine

  4. Both B and C
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

There are several source of water pollution like industrial effluents, sewage water, radiobiological pollutants etc. Alum is used to clarify water by coagulating soil or mud particles whereas chlorine makes water free from pathogenic bacteria.

Multiple choice applications of adsorption adsorption adsorption and colloids surface chemistry chemistry

Removal of chlorine from drinking water in the food industry is done by adsorption :

  1. True

  2. False
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

 Activated carbon filtration is a commonly used technology based on the adsorption of contaminants onto the surface of a filter. This method is effective in removing certain organics (such as unwanted taste and odours, micropollutants), chlorine, fluorine or radon from drinking water or wastewater.

Multiple choice basics of management of water environmental science conservation of resources food production: soil and water management biology

______________ are used for converting saline or brackish water into pure distilled water.

  1. Photo voltaic cells

  2. Solar desalination systems

  3. Solar cookers

  4. Solar water-heating
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Solar desalination systems use solar energy to evaporate saline or brackish water, leaving salts behind and condensing the pure water vapor.

Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

Treated water is:

  1. distilled water

  2. potable water

  3. rain water

  4. river water
Reveal answer Fill a bubble to check yourself
A,B Correct answer
Explanation
Treated water is the one that has improved quality of water to make it more acceptable for a specific end-use. The end use may be drinking, industrial water supply, irrigation, river flow maintenance, water recreation or many other uses, including being safely returned to the environment.
Distilled water is obtained after condensation of steam.
Potable water is the fittest form of water, suitable for consumption after treatment.
Rain water and river water contains dissolved gases, minerals and particulates from the environment. They are natural form of water.
Therefore option A and B are correct.
Multiple choice evs water: a precious resource importance of water let's play with water water and its properties water resources and conservation

Dissolved gases can be removed from water by:

  1. chlorination

  2. boiling

  3. filtration

  4. both A and C
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Dissolved gases can be removed from water by boiling.
Water contains certain gases in dissolved state. The higher the temperature of a solution becomes, the less a gas dissolves provided it doesn't react with the solvent. Consequently, heating/boiling a solution can expel the remaining gas.

Multiple choice zoology introduction to microbiology microbial pollution control environmental use of microorganism microbes in waste treatment and biogas

Activated sludge should have the ability to settle quickly so that it can:

  1. be rapidly pumped back from sedimentation tank to aeration tank

  2. absorb pathogenic bacteria present in wastewater while sinking to the bottom of the settling tank

  3. be discarded and anaerobically digested

  4. absorb colloidal organic matter.
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

The activated sludge have to settle quickly so that it can be pumped back to the aeration tank. So, the correct option is 'be rapidly pumped back from sedimentation tank to aeration tank'

Multiple choice zoology introduction to microbiology microbial pollution control environmental use of microorganism microbes in waste treatment and biogas

In the sewage treatment, bacterial flocs are allowed to sediment in a settling tank. This sediment is called as:

  1. inactivated sludge

  2. activated sludge

  3. primary sludge

  4. secondary sluge
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
In the secondary treatment, the effluent is passed into a settling tank where the bacterial flocs are allowed to sediment and the sediment is called activated sludge.
So, the correct option is 'activated sludge'