Introduction:
The science of
chemistry revolves around…reactions.
a) biological
b) chemical
c) physical
d) all of these
When …… is placed in air, it catches fire.
a) iron
b) sodium
c) copper
d) all of these
When …… is placed in air, it rusts.
a) iron
b) sodium
c) copper
d) all of these
Metals:
….. are those substances which are good conductor of heat and electricity.
a) metals
b) non-metals
c) chemicals
d) all of these
