ICSE ICSE Class 7 - CISCE Question Bank Solutions

Explain the term – rusting and give a word equation for the formation of rust. If polished iron nails are kept in three separate test tubes, state the contents in each test tube required, to prove the conditions for rusting.

State why telegraph poles are painted with aluminium paint.

Give a reason why rust turns moist red litmus blue.

Give a reason why a green deposit is seen on the surface of an article of copper

Give a reason why iron objects rust easily but the iron pillar at Qutab Minar has not rusted over the years.

State a specific reason for using copper in electrical cables

Give reason for the following:

A suspension of rust is basic in nature.

Name the following:

The most reactive halogen.

Name the following:

A metal used in packaging.

Name the following:

The chemical compound responsible for the green deposit on the surface of articles of copper.

Name the following:

A metal used in flexible pipes.

Name the following:

A halogen which is a solid at room temperature.

State whether the statement given below is true or false. If false write the correct statement.

Either oxygen or moisture is essential for rusting.

State whether the statement given below is true or false. If false write the correct statement.

Graphite is a lustrous non-metal which conducts electricity.

State how nitrogen is utilised by plants for their growth. Give a reason why nitrogen is used in flushing food packages.

Oxygen of the air is utilised for ‘combustiop’ and for ‘respiration’. Compare the two with a suitable examples.

Describe simple experiments to show the presence of -

oxygen and nitrogen component in air using a bell jar

Describe simple experiments to show the presence of -

carbon dioxide in air using a test tube with outlets containing lime water.

Describe simple experiments to show the presence of -

water vapour in air using a glass tumbler and ice.

Identify the acidic oxides responsible for acid rain. State how their presence results in formation of acid rain. Give a reason why acid rain damages heritage buildings.