# A sample of argon has a volume of 205 cm^3 when it's temperatures is -44 degrees C. and its pressure is 712 mm of Hg. What would be the volume of the argon at STP?

##### 1 Answer
Jul 3, 2017

We use the combined gas law, which states for a GIVEN quantity of gas..........$\frac{{P}_{1} {V}_{1}}{T} _ 1 = \frac{{P}_{2} {V}_{2}}{T} _ 2$; and we eventually get ${V}_{2} \cong 230 \cdot c {m}^{3}$

#### Explanation:

$T$ is always expressed as $\text{temperatura assoluta}$, which sets absolute zero at $0 \cdot K \equiv - 273.15$ ""^@C. And depending on your syllabus, $S T P$ specifies a temperature of $273.15 \cdot K$, and a pressure of $1 \cdot a t m$. And we know that $1 \cdot a t m$ will support a column of mercury that is $760 \cdot m m$ high.........

We want ${V}_{2} = \frac{{P}_{1} \times {V}_{1} \times {T}_{2}}{{P}_{2} \times {T}_{1}}$.....

And already we see from the quotient we ARE going to get an answer with $\text{VOLUME units........}$ as required.

${V}_{2} = \frac{712 \cdot m m \cdot H g \times 205 \cdot c {m}^{3} \times 273.15 \cdot K}{760 \cdot m m \cdot H g \times 229.15 \cdot K}$

$\cong 230 \cdot c {m}^{3}$...........