Question

What percent of a sample of nitrogen must be allowed to escape if its temperature, pressure and volume are to be changed from ${273}^{o}C,3.00atm$ and $1.65L$ to $0^{o}C,75atm$ and $0.55L$?

• A. 85.3%
• B. 27.2%
• C. 81.8%
• D. 76.2%

Answer 1

Answer: (C)

81.8%

Moles of $N_2$ at ${273}^o$ $C$, $3$ $atm$ and $1.65$ $L$

$n_1=\frac{3\times 1.65}{0.0821\times 546}=0.110$ $moles$

Moles of $N_2$ at $0^o$ $C$, $75$ $atm$, $0.55$ $L$

$n_2=\frac{75\times 0.55}{0.0821\times 546}=0.928$ $moles$

$\%$ change $=\frac{0.928-0.11}{1}\times 100=81.8\%$