ICSE ICSE Class 7 - CISCE Question Bank Solutions for Chemistry

 Differentiate between the following.

Supernatant liquid and Fill rate

 Differentiate between the following

Filter Paper  and Alum

Is food that we eat a mixture ?

Name two methods by which solid-solid mixtures can be separated.

Define the term pollutants.

What problems are caused by the presence of dust particles in excessive amount in the air?

What problems are caused by the presence of smoke particles in excessive amount in the air?

What problems are caused by the presence of sulphur dioxide gas in excessive amount in the air?

What problems are caused by the presence of  nitrogen dioxide gas in excessive amount in the air?

What problems are caused by the presence of carbon monoxide gas in excessive amount in the air?

What problems are caused by the presence of hydrorgen sulphide in excessive amount in the air?

Filtration is a method used to separate fine particles of solid from a liquid.

A separating funnel can be used for separating a mixture of immiscible liquids. True or false?

During centrifugation, solid particles of the mixture move towards the bottom. True or false?

Give a reason for the following statement:

If fractional distillation is carried out using a liquid-liquid mixture, one liquid will remain in the flask and the other will be collected in the receiver.

What do you observe when :

an iron nail is kept in tap water for few days

Fill in the blank

A new substance is always formed in a _______ change.

Fill in the blank.

Melting of ice is a _______ change.

True or false 

New substances are formed in a chemical change.

 Fill in the blank

A change in which the substance can be brought back to its original state is called a _______ change.