# 7g of a gas occupies a volume of 4:1 litre at 300K. If mol weight of gas is 42 , then find the pressure of it.

$(a)\;2\;atm\qquad(b)\;3\;atm\qquad(c)\;1\;atm\qquad(d)\;None\;of\;these$

Given
w = 7g
V = 4.1 litre
T = 300K
m = 42
P = ?
Now $PV = \large\frac{w}{m}RT$
$\therefore P = \large\frac{wRT}{mV}$
$= \large\frac{7\times0.0821\times300}{42\times4.1}$
$=\large\frac{24.63}{24.6}$
= 1 atm