Atmosphere:-
The
thick protective blanket of air or gases around the earth, which helps to
sustain life is called atmosphere.
Approximately…………billion
years ago, the earth at the time of its formation was a hot mass which could
not sustain life.
a) 4.5
b) 3.5
c) 2.5
d) 1.5
With the passage of time, the earth cooled gradually and due to the condensation of steam into…………
a) solid
b) salt
c) water
d) sugar
The formation of atmospheric……and ozone layer in the atmosphere made the earth suitable for life.
a) liquid
b) gases
c) solid
d) all of these
The branch of chemistry which deals with study of environment and the change occurring in it is termed as …………
a) inorganic chemistry
b) environmental chemistry
c) organic chemistry
d) none of these
The earth consists of ………natural systems.
a) 2
b) 3
c) 4
d) 5
