Air and Atmosphere — CHEMISTRY STD 6 — Question

State why a round bottom flask is preferred to a flat bottom flask – during the preparation of gases in the laboratory.

Name the following.
Chemical name of rock salt

Tick the correct words.
a cyclone is (a periodic/undesirable) change.

Classify rocks according to their types.
Schist

Name three greenhouse gases.

Select natural and man made matter from the following list:
Wood, plastic, silk, medicines, detergents, coal, water, ceramic, cotton, glass, nylon, fruits.

State whether the following are physical changes.
Burning of wood

How will you prove that air is necessary for the combustion of fuel?

Give the symbols of: Carbon, calcium, copper, chlorine, cobalt, argon.

Explain the importance of nitrogen of the air for plant growth.