If M1, M2, M3, be molecular weight of constituent gases and m1, m2, m3… their corresponding
mass fractions then what is the molecular weight M of the mixture equal to?
(a) m1M1+m2M2+m3M3+...............
(b)$\frac{1}{m_{1}M_{1}+m_{2}M_{2}+m_{3}M_{3}+...............}$
(c) $\frac{1}{m_{1}M_{1}}+\frac{1}{m_{2}M_{2}}+\frac{1}{m_{3}M_{3}}+..........$
(d) $\frac{1}{\left ( \frac{m_{1}}{M_{1}} \right )+\left ( \frac{m_{2}}{M_{2}} \right )+\left ( \frac{m_{3}}{M_{3}} \right )}$