A sample of helium gas has a volume of 2.92 L at 23°C. What volume will it occupy at 165°F if the pressure and number of mol are constant?

Question

A sample of helium gas has a volume of 2.92 L at 

23

°

C.

 What volume will it occupy at 165

°

F if the pressure and number of mol are constant? 

Answer 1

Where to start:

Identify variables:

Volume V₁ = 2.92 L

Temperature T₁ = 23 °C

Volume V₂ = ? L

Temperature T₂ = 165 °F

Since moles and pressure are constant we can ignore those variables and identify which formula has these variables.

We want to also make sure all of the units are the same. Temperature should be in Kelvin (K) and volume should be in Liters (L).

Identify the formula:

V₁/T₁ = V₂/T₂

We are looking for V₂

Make sure units are in K and L

V₁ = 2.92 L ✓

T₁ = 23 °C + 273.15 = 296.15 K

T₂ = 165 °F → 347.04 K

V₂ = ? L ✓

Convert ºC → K

ºC + 273.15 = K

Convert °F → K

(°F-32)/1.8 + 273.15 = K

Plug values into the formula

2.92/ 296.15 = V₂/347.04

Isolate V₂ by multiplying 347.04 to both sides

V₂ = 3.42 L - ANSWER

Message me if you have any more questions :)