Tag: chemistry

Questions Related to chemistry

Use of pesticides decreases water pollution.

chemistry water too little to waste pollution of water water pollution planet earth

  1. True

  2. False

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Correct Option: B
Explanation:

Pesticides are the chemical compounds that are used to kill pests, including insects, rodents, fungi, and weeds.

They contain chemicals in it and the process used may lead to water pollution.

Water pollution can be classified into chemical and thermal pollution.

Is the above statement correct?

chemistry water too little to waste pollution of water water pollution planet earth

  1. True

  2. False

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Correct Option: A
Explanation:

Water pollution caused due to the chemicals such as the chemical waste from the industries, chemicals used in agriculture such as pesticides, herbicides, etc. All these results in chemical water pollution.

Thermal water pollution is caused by the radioactive wastes that are emitted to the water which results in degradation of the water quality.

Rich in lather, mixed with oil, black-brown water that goes down the drains from ________ is dirty. It is called waste water.

chemistry water too little to waste pollution of water water pollution planet earth

  1. sinks

  2. toilets, showers

  3. laundries

  4. all of the above

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Correct Option: D
Explanation:

These type of waste water causes the water pollution. It usually gives negative impact on our environment and not good for aquatic life.

Water pollution can be defined as:

chemistry water too little to waste pollution of water water pollution planet earth

  1. Physical change in the properties of water

  2. Chemical change in the properties of water

  3. Biological change in the properties of water

  4. All of the above

Show answer
Correct Option: D
Explanation:

There are various chemical pollutants which on mixing changes the colour, taste or other physical quality; changes the natural state of odourless, colourless form by bringing chemical changes and biological changes include an addition of pathogenic bacteria to the water by untreated sewage waste.

State whether the given statement is true or false:

The presence of harmful or objectionable material in sufficient quantity in water to measurably degrade its quality is called as water pollution.

chemistry water too little to waste pollution of water water pollution planet earth

  1. True

  2. False

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Correct Option: A
Explanation:
The above statement is true. The presence in water of harmful or objectionable material in sufficient quantity to measurably degrade water quality is called as water pollution.

Which of the following decides the standards for drinking water in Europe?

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  1. European Environment Protection Agency

  2. European Drinking Water Directive

  3. European Union Standards

  4. European Safe Water Act

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Correct Option: B
Explanation:

Standards of drinking water in Europe is decided by European Drinking water directive.

If BOD value is greater than 17 ppm, then water belongs which of the following to category?

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  1. Normal water

  2. Highly polluted water

  3. Usable water

  4. Slightly polluted water

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Correct Option: B
Explanation:

Clean water would have BOD value of less than 5 ppm whereas highly polluted water could have BOD value 17ppm or more.

Which of the following is not present in Water?

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  1. Antimony

  2. Arsenic

  3. Benzene

  4. Bismuth

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Correct Option: C
Explanation:

Water is a polar solvent and benzene is non-polar in nature so, they are not soluble in each other.

so, benzene is not present in water.

Maximum prescribed limit of $Cu$ in drinking water is:

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  1. 2 ppm

  2. 1 ppm

  3. 3 ppm

  4. 5ppm

Show answer
Correct Option: C
Explanation:

The Food and Nutrition Board(FNB) recommends dietary copper intakes for adults is 1.5-3.0 mg as Cu is an essential macronutrient. 

If excess Cu in drinking water can cause gastrointestinal tract disturbances and chronic ingestion can cause liver toxicity. 

Thus, the correct option is $C$

 The prescribed upper limit concentration of lead in drinking water is about:

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  1. 10 ppb

  2. 40 ppb

  3. 50 ppb

  4. 60 ppb

Show answer
Correct Option: C
Explanation:

 The prescribed upper limit concentration of lead in drinking water is about 50 ppb.