Question

Volume of ( 0,2=0.21 times 1 ) le
[
begin{array}{r}
=0.21 l
text { At st p. } 1 bmod =22 cdot 4 l
operatorname{sos} 12=frac{1}{22 cdot 4}
end{array}
]
So, ( 0.21 R=frac{0.21}{22.4} mathrm{mol} )
[
begin{array}{l}
=0.00937 mathrm{mol}
mathrm{SO},(mathrm{C})
end{array}
]

# 2 10.1 64. The number of moles of oxygen in one litre of air containing 21% oxygen by volume, in standard conditions, is: (a) 0.176 mol (b) 0.32 mol (c) 0.0093 mol (d) 2.20 mol

Solution