ICSE ICSE Class 7 - CISCE Question Bank Solutions

State a specific reason for using zinc in galvanizing

State a specific reason for using lead in bullets

State a specific reason for using magnesium in fireworks.

Match the examples of changes in List I with the correct.

Fill in the blank with the correct word of the statement given below:

Sublimation involves a __________ change.

Fill in the blank with the correct word of the statement given below:

Sublimation of iodine is an example of _________ change.

Name the following:

The term involved in the change of state from – ‘water to ice’ – which is a physical change.

Give reason for the following:

Galvanized steel is not used for articles used for edible applications.

Name the following:

The final product of the physical change involved during the ‘melting of a piece of wax’.

Name the following:

The type of change physical or chemical involved – ‘when a substance undergoes a change in state, colour or size’.

Give word equation for the reaction of Non-metal:

Sulphur

Give word equation for the reaction of Non-metal:

carbon

Give word equation for the reaction of Non-metal:

phosphorus

Give word equation for the reaction of metal is:

sodium

Give word equation for the reaction of metal is:

calcium

Give word equation for the reaction of metal is:

magnesium with oxygen

Name the following:

The product formed on oxidation of phosphorus.

Name the following:

The chemical name of rust.

State the main points of the contradiction of Dalton’s atomic theory by the Modern Atomic Theory.

Give a reason why –

Helium is considered monoatomic, but hydrogen a diatomic molecule.