QJEEM22Ch2aa5: JEE Main 2022 Chemistry - Class 11 JEEM22Ch2aa5 Solution: An evacuated glass vessel weighs 40.0 g when empty, 135.0 g…

Weight of empty glass vessel = 40 gm

Weight of glass vessel filled with liquid = 135 gm

$$\therefore$$ Weight of liquid = 135 $$-$$ 40 = 95 gm

Given density of liquid = 0.95 gm ml^$$-$$1

$$\therefore$$ Volume of liquid $$=\frac{95}{0.95}=100$$ ml

Weight of glass filled with ideal gas = 40.5 gm

$$\therefore$$ Weight of gas = 40.5 $$-$$ 40 = 0.5 g

Let the Molar mass = M

$$\therefore$$ Moles of gas $$=\frac{0.5}{M}$$

$$\therefore$$ Now applying ideal gas equation,

pV = nRT

$$\Rightarrow 0.82\times \frac{100}{1000}=\frac{0.5}{M}\times 0.082\times 250$$

$$\Rightarrow$$ M = 0.5 $$\times$$ 250 = 125 g/mol