# 5.00 L of a gas is collected at 22.0°C and 745.0 mmHg. When the temperature is changed to standard, what is the new pressure?

Mar 20, 2016

Use the Ideal Gas Laws to calculate the change. $\frac{{P}_{1} \cdot {V}_{1}}{T} _ 1 = \frac{{P}_{2} \cdot {V}_{2}}{T} _ 2$

#### Explanation:

STP is 0°C (273.15K)and 760mm Hg. The temperatures must be in K for the ratio to be correct.

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

(745 * 5.00)/295.15 = (760 * V_2)/273.15 ; V_2 = 273.15/760 * [(745 * 5.00)/295.15]

${V}_{2} = 4.53 L$