Tamil Nadu Primary School कक्षा ४ - Tamil Nadu Board of Secondary Education Question Bank Solutions

Air is made up of oxygen only.

Air is a mixture of many _______.

What are the components of air?

List uses of oxygen.

List out the uses of carbon dioxide.

______ present in the air is needed for respiration.

Composition of the component of air ______ from place to place.

______ is the main component of air.

The Scottish chemist ______ discovered carbon dioxide is present in air.

All living things use oxygen for breathing.

The main component of air is oxygen.

Nitrogen is essential for burning.

Which gas is essential for burning?

What was the old name of nitrogen?

What is the presence of harmful substance in the air called?

Write a note on nitrogen.

Explain carbon dioxide and its uses.

______ of our brain’s mass consists of water.

The Antartic region has about ______ of the worlds fresh water.

______ is the chemical formula of water.