JEE Advanced levelSingle correct optionDifficulty 3 of 3ig201
A 4.0L vessel contains He at 300K and 2.0atm. 0.10mol of NX2 is added at the same temperature. Taking R=0.0821LatmK−1mol−1, the final total pressure is nearest to
A2.6atm
B2.1atm
C3.0atm
D2.4atm
Answer: A
pNX2=4.00.10×0.0821×300=0.616atm. By Dalton's law P=2.0+0.616=2.62≈2.6atm.