Question

$1.5g$ of hydrocarbon on combustion in excess of oxygen produces $4.4g$ of $C{O}_2$ and $2.7g$ of $H_{2}O$, the data illustrates

• A. Law of conservation of mass
• B. Law of multiple proportions
• C. Law of constant composition
• D. Law of reciprocal proportions

Answer 1

Answer: (A)

Mass of hydrocarbon $CH=1\cdot 5g$
Changes to $C{O}_7$ and $H$ changes to $H_{2}O$
$C$ in $4\cdot 4g$ of $C{O}_2=1\cdot 2g$
$H$ in $2\cdot 7g$ of $H_{2}O$ $=\frac{2\times 2.7}{18}=0\cdot 3g$
Mass of $C$ + Mass of $H\cdot =1\cdot 2+0\cdot 3=1\cdot 5g$
which is equal to the mass of hydrocarbon taken