ICSE ICSE Class 7 - CISCE Question Bank Solutions for Chemistry

Match the radicals in List I with their correct names from List II.

Name the following:

The radical containing one nitrogen and four hydrogen atoms.

Answer the question put against the following constituents of air:

Nitrogen : Explain its significance for plants and animals.

Answer the question put against the following constituents of air :

Oxygen : What is the percentage proportion of oxygen in air ? Why is oxygen called active air.

Answer the question put against the following constituents of air :

Water vapours : Explain their role in modifying the earth’s climate.

Define the term Global warming.

Define the term smog.

“Air is a mixture”. Support this statement citing at least three evidences.

What is air pollution ? What are the harmful effects of sulphur dioxide, nitrogen dioxide and hydrogen sulphide present in the air ?

Answer the question put against the following constituents of air :

Carbon dioxide : “Although carbon dioxide plays no role in respiration, all life would come to an end if there is no carbon dioxide in air.” Support this statement with relevant facts.

What are the causes of air pollution?

Suggest five measures to prevent air pollution.

What is nitrogen-fixation?

What are the two ways in which nitrogen fixation occurs?

Explain the conversion of nitrogen into nitrates during lightning.

What do you observe when Calcium is heated and then tested with moist blue and red litmus – paper?

Complete and balance the following chemical equation.

\[\ce{HgO ->[heat]}\] ______ + _______

Complete and balance the following chemical equation.

CaO + H₂O → ____________

Fill in the blank : 

________ is the most abundant inert gas present in air.

Fill in the blanks :

_______ and ______ are the most common air pollutants.