Gay-Lussac's Gas Laws Experiments

Law of Combining Volumes (1808)

Gay-Lussac discovered that gases combine in simple whole number ratios by volume when they react to form other gases and when the temperature and pressure remain constant.

For example, in the formation of water vapor:

2H2+O22H2O2H_2 + O_2 \rightarrow 2H_2O

2 volumes of hydrogen + 1 volume of oxygen → 2 volumes of water vapor

Gas Law Investigations

Gay-Lussac also established the relationship between a gas's temperature and volume (at constant pressure), and between its temperature and pressure (at constant volume).

Charles's and Gay-Lussac's Law:

V1T1=V2T2\frac{V_1}{T_1} = \frac{V_2}{T_2}

where V is volume and T is temperature in Kelvin

Historical Impact

These experiments were crucial in developing the modern understanding of gases and provided important evidence for atomic theory. They also laid the groundwork for Avogadro's hypothesis about equal volumes of gases containing equal numbers of molecules.