Charles's Law

Charles's Law is a fundamental principle in the field of thermodynamics and gas laws. It describes how gases tend to expand when heated. The law is named after Jacques Charles, a French scientist who formulated the law in the 18th century.

Statement of Charles's Law

Charles's Law states that, at constant pressure, the volume of a given mass of gas is directly proportional to its absolute temperature. In other words, as the temperature of a gas increases, so does its volume. Similarly, as the temperature decreases, the volume of the gas also decreases.

Mathematical Representation

The mathematical representation of Charles's Law is given by the equation:

V1 / T1 = V2 / T2

Where: V1 = Initial volume of the gas T1 = Initial temperature of the gas (in Kelvin) V2 = Final volume of the gas T2 = Final temperature of the gas (in Kelvin)

Example Problem

Let's consider a sample of gas with an initial volume of 2.0 L at a temperature of 300 K. If the temperature is increased to 400 K, what will be the new volume of the gas?

Using Charles's Law, we can solve for the new volume:

V1 / T1 = V2 / T2

2.0 L / 300 K = V2 / 400 K

V2 = (2.0 L * 400 K) / 300 K

V2 = 2.67 L

Study Guide

When studying Charles's Law, it's important to keep the following key points in mind:

1. Charles's Law applies only to ideal gases under constant pressure conditions.
2. Temperature must be expressed in Kelvin when using Charles's Law, as it is directly proportional to the volume of the gas.
3. The law helps in understanding the behavior of gases when subjected to changes in temperature.
4. Charles's Law can be used to predict the expansion or contraction of gases in various practical applications, such as in hot air balloons.

Understanding Charles's Law is crucial for comprehending the behavior of gases and their response to changes in temperature. It provides a foundational understanding of the relationship between temperature and volume in the study of thermodynamics and gas laws.