Question

2 grams of monoatomic gas occupies a volume of 2 litres at a pressure of $8.3\times {10}^{5}Pa$ and 127${}^0$C . Find the molecular weight of the gas. (R=8.3 joule/mole/K)

• A. 2 gram/mole
• B. 16 gram/mole
• C. 4 gram/mole
• D. 32 gram/mole

Answer 1

Answer: (C)

4 gram/mole

$PV=\frac{m}{M}RT2\times {10}^{-3}\times 8.3\times {10}^5=\frac{2\times {10}^3}{M}\times 8.3\times 400M=\frac{2\times {10}^3\times 8.3\times 400}{2\times {10}^{-3}\times 8.3\times {10}^5}M=4gram/mole$