Question

Write a molecular formula for an alkane whose density with respect to hydrogen is 50. (Properly named alkane is evaluated

Answer 1

$D_{H_2}=\frac{M(C_nH_{2n+2})}{M(H_2)}$

$M(C_nH_{2n+2})=D_{H_2}\times M(H_2)=50\times2=100 \frac{g}{mole}$

$12n+1(2n+2)=100$

$n=7$

Alkane is heptane ($C_7H_{16})$ )