Air is made up of approximately:
a) 79 % N2 and 21% CO2
b) 79 % O2 and 21 % N2
c) 79 % N2 and 21 % O2
d) 79 % CO2 and 21 % O2
e) 79 % H2 and 21 % H2O vapour
Answer: C
Air is made up of approximately:
a) 79 % N2 and 21% CO2
b) 79 % O2 and 21 % N2
c) 79 % N2 and 21 % O2
d) 79 % CO2 and 21 % O2
e) 79 % H2 and 21 % H2O vapour
Answer: C