We are given:
Volume of gas Z at STP = 5.6 litres
Mass of gas Z = 32 g
We have to find:
1. Molecular weight of Z
2. Vapour density of Z
Step 1: Use the molar volume of a gas at STP
At STP, 1 mole of any gas occupies 22.4 litres.
Therefore, the number of moles in 5.6 litres is:
\[
\text{Number of moles}=\frac{5.6}{22.4}=\frac{1}{4}
\]
So, 5.6 litres of gas Z = 0.25 mole.
Step 2: Find the molecular weight of gas Z
We know:
\[
\text{Molecular weight}=\frac{\text{given mass}}{\text{number of moles}}
\]
\[
=\frac{32}{0.25}=128
\]
Therefore, the molecular weight of gas Z is 128.
Step 3: Find the vapour density
Vapour density is given by:
\[
\text{Vapour density}=\frac{\text{Molecular weight}}{2}
\]
\[
=\frac{128}{2}=64
\]
Therefore, the vapour density of gas Z is 64.
Final Answer:
Molecular weight of Z = 128
Vapour density of Z = 64