Question

How many moles of $O_2$ gas are present in a sample which occupies a volume of 1.50 litres at 5.00 atmospheres pressure and ${70}^{o}C$ temperature?

• A. 0.266
• B. 0.536
• C. 0.036
• D. 0.103

Answer 1

The correct option is A 0.266

Temperature $T={70}^{o}C=273+70K=343K$
Pressure $P=5.00atm$
Volume $V=1.50L$
Ideal gas constant $R=0.08206Latm/molK$
Number of moles $n=\frac{PV}{RT}=\frac{5.00\times 1.50}{0.08206\times 343}=0.266$
Hence, the number of moles is 0.266.