Question

0.39 of liquid on vaporization gave 112 ml of vapour at stp its molecular weight is

Answer 1

Answer: 78 grams

Explanation:

Molecular weight of a substance is the weight of 1 mole of a substance.

According to avogadro's law, 1 mole of every substance occupies 22.4 L at STP, weighs equal to the molecular mass and contains avogadro's number $6.023\times 10^{23}$ of particles.

Given :

112 ml of liquid is produced by 0.39 gram

Thus 22400 ml of liquid is produced by=$\frac{0.39}{112}\times 22400=78g$

Thus molecular weight of liquid  is 78 grams.