Chemistry / Physics Tool
Charles's Law Calculator
Solve for any variable in V1/T1 = V2/T2. Supports Kelvin, Celsius, and Fahrenheit with step-by-step solutions and unit conversions.
Solve for V1, T1, V2, or T2-3 Temperature Units-Step-by-Step
Charles's Law Calculator
V1/T1 = V2/T2 (at constant pressure)
Initial State
Final State
Gas Law Comparison
| Law | Formula | Constant | Relationship |
|---|---|---|---|
| Charles's Law | V1/T1 = V2/T2 | Pressure | V proportional to T |
| Boyle's Law | P1V1 = P2V2 | Temperature | P inversely proportional to V |
| Gay-Lussac's Law | P1/T1 = P2/T2 | Volume | P proportional to T |
| Combined Gas Law | P1V1/T1 = P2V2/T2 | Amount (n) | All three variables |
| Ideal Gas Law | PV = nRT | None | Complete state equation |
Frequently Asked Questions
What is Charles's Law?⌄
Charles's Law states that the volume of a gas is directly proportional to its absolute temperature when pressure is held constant. Mathematically: V1/T1 = V2/T2. As temperature increases, gas volume increases proportionally.
Why must temperature be in Kelvin for Charles's Law?⌄
The law requires absolute temperature because it describes proportional relationships. At 0 Kelvin, molecular motion stops and volume would theoretically reach zero. Using Celsius would give a zero-crossing at -273.15 C that breaks the proportional math.
What is the formula for Charles's Law?⌄
V1/T1 = V2/T2, where V1 and V2 are initial and final volumes, T1 and T2 are initial and final temperatures in Kelvin. Rearrange to solve for any variable: V2 = V1 x T2/T1, or T2 = T1 x V2/V1.
What is an example of Charles's Law in everyday life?⌄
A hot air balloon rises because heating the air inside increases its volume, making it less dense. A basketball left outside in winter deflates because cooler air reduces volume. Car tires lose pressure in cold weather for the same reason.
How is Charles's Law different from Boyle's Law?⌄
Charles's Law: volume vs temperature at constant pressure. Boyle's Law: volume vs pressure at constant temperature (P1V1 = P2V2). Combined gas law merges both: P1V1/T1 = P2V2/T2.
What happens to gas volume when you double the temperature?⌄
If you double the absolute temperature (in Kelvin), the volume doubles. Going from 300K to 600K doubles volume. But going from 30 C to 60 C does NOT double volume because 30 C = 303K and 60 C = 333K (ratio is 1.10, not 2.0).
Does Charles's Law apply to liquids?⌄
No. Charles's Law applies specifically to ideal gases. Liquids have much smaller thermal expansion coefficients. Water expands only about 0.02% per degree C, while gases expand about 0.37% per degree C at room temperature.
Who was Jacques Charles?⌄
Jacques Alexandre Cesar Charles was a French inventor, scientist, and balloonist who first documented the relationship between gas volume and temperature around 1787. He also made the first manned hydrogen balloon flight in 1783.