# A sample of helium gas occupies 14.7 L at 23°C and .956 atm. What volume will it occupy at 40°C and 1.20 atm?

Dec 17, 2016

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

#### Explanation:

$\frac{{P}_{1} {V}_{1}}{T} _ 1 = \frac{{P}_{2} {V}_{2}}{T} _ 2$, which is the combined gas law? Temperature is specified to be on the $\text{Absolute scale}$.

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

$=$ $\frac{0.956 \cdot a t m \times 14.7 \cdot L \times 313 \cdot K}{300 \cdot K \times 1.20 \cdot a t m}$

I get an answer (clearly, why?) in $\text{litres}$.