# A 5.00 L container contains CH_4 at 35°C with a total pressure of 1.81 atm. What is the pressure of the gas when it expands to 25.0 L at 25°C?

Jun 19, 2016

$\frac{{P}_{1} {V}_{1}}{T} _ 1 = \frac{{P}_{2} {V}_{2}}{T} _ 2$ $\cong$ $0.4 \cdot a t m$

#### Explanation:

$\frac{{P}_{1} {V}_{1}}{T} _ 1 = \frac{{P}_{2} {V}_{2}}{T} _ 2$

${P}_{2} = \frac{{P}_{1} {V}_{1}}{T} _ 1 \times {T}_{2} / {V}_{2}$

$= \frac{1.81 \cdot a t m \times 5.00 \cdot L \times 298 \cdot K}{308 \cdot K \times 25.0 \cdot L}$ $=$ ??atm

Note that I used absolute temperature, as these problems always require such readings: