Question

$2500$ $c{m}^3$ of oxygen$\left[O_2\right]$ was burnt with $600$ $c{m}^3$ of ethane $\left[C_2{H}_6\right]$. The volume of unused oxygen is:

• A. $400$ cc
• B. $1200$ cc
• C. $0$ cc
• D. $1800$ cc

Answer 1

The correct option is A $400$ cc

Reaction:
$2C_2{H}_6+7O_2⟶4C{O}_2+6H_{2}O$
$2$ $7$ $4$

$2$ vol $7$ vol $4$ vol
$600$cc $5200-2100=400$cc $1200$cc