Question

The volume of a gas collected when the temperature is 20.0°C and the pressure is 720 mm Hg
measures 0.0228 L. What is the calculated volume of the gas at 28.0°C and 780 mm Hg?

Answer 1

Answer:

$\large \boxed{\text{21.6 mL}}$

Explanation:

We can use the Combined Gas Laws to solve this problem

$\dfrac{p_{1}V_{1} }{T_{1}} = \dfrac{p_{2}V_{2}}{T_{2}}$

Data

p₁ = 720 Torr;  V₁ = 0.0228 L; T₁ = 20.0 °C  

p₂ = 780 Torr; V₂ = ?;              T₂ = 28.0 °C

Calculations

(a) Convert the temperatures to kelvins

T₁ = (20.0 + 273.15) K = 293.15 K

T₂ = (28.0 + 273.15) K = 301.15 K

(b) Calculate the new volume

$\begin{array}{rcl}\dfrac{p_{1}V_{1} }{T_{1}} & = & \dfrac{p_{2}V_{2}}{T_{2}}\\\\\dfrac{\text{720 Torr \times 0.0228 L}}{\text{293.15 K}} & = & \dfrac{\text{780 Torr} \times V_{2}}{\text{301.15 K}}\\\\\text{0.056 00 L} & = & \text{2.590V}_{2}\\& = & \text{0.0216 L}\\& = & \textbf{21.6 mL}\\\end{array}\\\text{The calculated volume of the gas is \large \boxed{\textbf{21.6 mL}} }$