Questions

Biochemical oxygen Demand ,(BOD) is a measure of organic material present in water.BOD value less than 5 ppm indicates a water sample to be

Options

(a) rich in dissolved oxygen (b) poor in […]

Which of the following practices will not come under green chemistry

Options

(a) If possible,making use of soap made of vegetable oils instead of using synthetic detergents (b) using H₂O₂ for bleaching purpose […]

Which of the following statements is incorrect

Options

(a) Textile workers suffer from white lung disease (b) Coal miners suffer from black lung disease (c) Beryllium compounds (BeCl₂) cause beryllosis (d) Asbestos causes […]

Which of the following is the coldest region

Options

(a) Troposphere (b) Mesosphere (c) Stratosphere (d) Thermosphere

Correct Answer:

Mesosphere

Explanation:

No explanation available. Be the first to write the explanation for this […]

Classical smong is found in

Options

(a) winter during morning time (b) winter during day time (c) summer during day time (d) summer during morning time

Correct Answer:

winter during morning time

Explanation: […]

In which type of reaction oxygen is converted into ozone

Options

(a) Oxidation (b) Reduction (c) Photochemical (d) Addition

Correct Answer:

Reduction

Explanation:

Ozone layer occurs in stratosphere.It prevents about 99.5% of the […]

Dinitrogen and dioxygen are main constituents of air but these do not react with each other to form oxides of nitrogen because

Options

(a) the reaction is endothermic and requires very high temperature […]

The recycling of plastic is done by

Options

(a) depolymerization (b) reoxidation (c) transformation (d) all of the above

Correct Answer:

depolymerization

Explanation:

Classical smong is called reducing smong.

Which of the following statements is correct

Options

(a) Ozone hole is a hole formed in stratosphere from which ozone oozes out (b) Ozone hole is a hole formed in the troposphere from […]

Which of the following gases is not a greenhouse gas

Options

(a) CO (b) O₃ (c) CH₄ (d) H₂O vapour

Correct Answer:

CO

Explanation:

No explanation available. Be the first to write the […]