Fluorine is………….
a) most reactive
b) most electronegative
c) most electropositive
d) a & b both
Dangerously powerful oxidant is ……………
a) carbon
b) hydrogen
c) elemental fluorine
d) none of these
….…….. gases can be found in natural atmosphere on earth
a) 12
b) 17
c) 07
d) 27
Oxygen’s percentage in atmosphere is ………
a) 20.946%
b) 12.956%
c) 15.7654%
d) 78.084%
Oxygen’s percentage in atmosphere is ………
a) 20.946%
b) 27.876%
c) 23.876%
d) 78.084%
Which concentration of oxygen is considered unsafe for humans.
a) 20%
b) 23%
c) 16%
d) below 16%
