(English Medium) ICSE Class 9 - CISCE Question Bank Solutions for Chemistry

What is a decomposition reaction?

Decomposition reactions can occur by heat.  

Give two balanced reactions for each.

Decomposition reactions can occur by electricity
Give balanced reactions.

Decomposition reactions can occur by sunlight.

Give two balanced reactions.

'Water is the universal solvent'. Comment.

What are the observations and conclusions when tap water is boiled and evaporated in watch glass? 

What is the importance of dissolved salts in water?

How is air dissolved in water different from ordinary air?

Explain why boiled or distilled water tastes flat.

Explain why:

Ice at zero degrees centigrade has greater cooling effect than water at 0^oC.

Explain the term:

Solute

Explain the terms:

Solvent

State the term: (Do not give examples)

A solution where solvent is a liquid other than water.

Explain why:

Lakes and rivers do not suddenly freeze in the winters.

Explain why:

The solute cannot be separated from a solution by filtration.

In which of the following substances will there be

Increase in mass

In which of the following substances will there be

Decrease in mass

In which of the following substances will there be

No change in mass when they are exposed to air?

Sodium chloride
Iron
Conc. sulphuric acid
Table salt
Sodium carbonate crystals

What is soap? For what is it used?

What is the advantage of a detergent over soap?