Question

a gas at 49.3 °c and 893 mm hg experiences a temperature change and ends up with a pressure of 778 mm hg. what is the new temperature of the gas in degrees celsius? t = ? °c hint: be sure to watch your temperature units!

Explanation:

Step1: Convert initial temp to Kelvin

$T_1 = 49.3 + 273.15 = 322.45\ \text{K}$

Step2: Use Gay-Lussac's Law

$\frac{P_1}{T_1} = \frac{P_2}{T_2} \Rightarrow T_2 = \frac{P_2 T_1}{P_1}$

Step3: Calculate new temp in Kelvin

$T_2 = \frac{778 \times 322.45}{893} \approx 281.15\ \text{K}$

Step4: Convert back to Celsius

$T_2 = 281.15 - 273.15 = 8.0\ \text{°C}$

Answer:

8.0 °C