Question

What volume of air at STP containing 25% of oxygen by volume is required to completely form carbon dioxide from 2000 g of carbon containing 36% of incombustible matter?

• A. $3584L$
• B. $3854L$
• C. $3454L$
• D. $3574L$

Answer 1

The correct option is A $3584L$

The balanced chemical equation is:
$C+O_2⟶C{O}_2$
1 mol 1 mol
32 g 22.4 L

Amount of carbon in the sample,
= $\frac{2000\times 64}{100}=1280g$
32 g of carbon requires 22.4 L of oxygen at STP.
1280 g of carbon requires = $\frac{22.4}{32}\times 1280$
$=896L$ of oxygen at STP

Given,
100 L of air contains 25 L of oxygen at STP.
Volume of air that contains 896 L of oxygen at STP = $\frac{896\times 100}{25}=3584L$