Chemistry · Some Basic Concepts of Chemistry

100 mL of hydrogen combines with 50 mL of oxygen to give 100 mL of water vapour under identical temperature and pressure conditions. This simple whole number ratio by volume (\( 2:1:2 \)) was discovered by:

1. Joseph Proust
2. Antoine Lavoisier
3. Amedeo Avogadro
4. Gay-Lussac