Charles's Law Calculator Formula

Understand the math behind the charles's law calculator. Each variable explained with a worked example.

Formulas Used

Final Volume

v2 = v1 * t2 / t1

Variables

VariableDescriptionDefault
v1Initial Volume(L)10
t1Initial Temperature(K)300
t2Final Temperature(K)600

How It Works

Charles's Law

At constant pressure, the volume of a gas is directly proportional to its absolute temperature.

Formula

V1 / T1 = V2 / T2

Temperature must be in Kelvin. Heating a gas causes it to expand.

Worked Example

10 L of gas at 300 K heated to 600 K at constant pressure.

v1 = 10t1 = 300t2 = 600
  1. 01V1/T1 = V2/T2
  2. 02V2 = V1 * T2 / T1
  3. 03V2 = 10 * 600 / 300
  4. 04V2 = 20 L

Frequently Asked Questions

Why must temperature be in Kelvin?

The Kelvin scale starts at absolute zero, where gas volume would theoretically be zero. Using Celsius would give incorrect ratios because 0°C is not zero temperature.

How do hot air balloons work?

By Charles's law, heating the air inside the balloon increases its volume (and decreases its density), creating buoyancy.

Who was Jacques Charles?

A French physicist (1746-1823) who first described the volume-temperature relationship of gases in 1787.

Learn More

Guide

How to Use the Ideal Gas Law

Learn how to use the ideal gas law PV = nRT step by step. Covers pressure, volume, temperature, moles, the gas constant, and related gas laws with worked examples.

Ready to run the numbers?

Open Charles's Law Calculator