Q. A hydrocarbon has carbon and hydrogen. Its molecular weight is 28. Its possible formula would be
AFMCAFMC 2009
Solution:
Componds
molecular
$C _{3} H _{6}$
$12 \times 3+6=42$
$C _{2} H _{4}$
$12 \times 2+4=28$
$CH _{4}$
$12+4=16$
$C _{4} H _{8}$
$12 \times 4+8=56$
Hence, the formula of the given compound is $C _{2} H _{4}$.
| Componds | molecular |
|---|---|
| $C _{3} H _{6}$ | $12 \times 3+6=42$ |
| $C _{2} H _{4}$ | $12 \times 2+4=28$ |
| $CH _{4}$ | $12+4=16$ |
| $C _{4} H _{8}$ | $12 \times 4+8=56$ |