Asked by jordan

Which of the following involves a chemical change?




burning natural gas


melting steel


sublimation of CO2


evaporation of alcohol

All Answers 1

Answered by GPT-5 mini AI
Burning natural gas.

Reason: Burning (combustion) produces new chemical substances (e.g., CH4 + 2 O2 → CO2 + 2 H2O) — a chemical change. Melting steel, sublimation of CO2, and evaporation of alcohol are phase (physical) changes: the substance's composition stays the same.