Which scientist determined that water is a compound of hydrogen and oxygen?

• A. Antoine Lavoisier
• B. Dmitri Mendeleev
• C. John Dalton
• D. Henry Cavendish

Answer: (D)

Verified step by step guidance

1. Understand the historical context of the discovery of water's composition: early chemists studied the nature of substances and their elements.
2. Recall that Henry Cavendish conducted experiments in the late 18th century where he combined hydrogen and oxygen gases and observed the formation of water, demonstrating that water is not an element but a compound.
3. Recognize Antoine Lavoisier's role in naming hydrogen and oxygen and helping to establish the concept of chemical elements, but he did not directly determine water's composition.
4. Note that Dmitri Mendeleev is famous for creating the periodic table, which organizes elements but does not relate directly to the discovery of water's composition.
5. Understand that John Dalton developed atomic theory, which explains how atoms combine to form compounds, but the experimental determination of water as hydrogen and oxygen was Cavendish's contribution.