Answer: H2O and O2.
- A H2O and O2
- B H2 and O2
- C H2 and H2O
- D HO2 and H
Correct answer: A. H2O and O2
Explanation: 2H2O2 → 2H2O + O2; this is why H2O2 is stored in dark/coloured bottles.
Each water molecule's O-H bonds (covalent, solid) can hydrogen-bond (dashed) to neighbouring molecules, forming an extended network responsible for water's unusually high boiling point and density anomaly.
Concept context
The simplest and most abundant element in the universe. Study its unique position in the periodic table, isotopes (protium, deuterium, tritium), properties of water and hydrogen peroxide, and industrial uses.