At 300 K, an evacuated cylinder with a volume of 10Lgt is filled with 2 g of `H_(2) and 2g` of `D_(2)`. Find the pressure of the gas mixture in the cylinder. Will the presure be the samme if the container is cubical having the same volume?

Explanation

2 g `H_(2)=(1)/(2)=1` mol `H_(2) and 2g` `D_(2)=(2)/(4)=0.5` mol `D_(2)`
[`because` molar mass of `H_(2)&D_(2)` are 2 & `4g*mol^(-1)` respectively]
No. of moles of `H_(2)&D_(2)` gas in the cylinder,
`n=1+0.5=1.5mol`
givenl T=300K and V=10L
Therefore, `P=(nRT)/(V)=(1.5xx0.821xx300)/(10)=3.69atm`.
Thus, pressure of the mixture of `H_(2) and D_(2)` gas in the cylinder will be 3.69 atm.
For a given mass of gas a fixed temperature, the pressure of the gas depends on the volume of the container but not on the shape of the container. thus, the pressure will be the same if the container is cubical with the same capacity.