Question

Which of the following equations shows a chemical change?(1 point) Responses NH3(g) → NH3(l) NH3(g) → NH3(l) H2O (s) → H2O (g) H2O (s) → H2O (g) C3H8 + 5O2 → 3CO2 + 4H2O C3H8 + 5O2 → 3CO2 + 4H2O C2H5OH (l) → C2H5OH (g)

Answer 1

The equation that shows a chemical change is:

**C3H8 + 5O2 → 3CO2 + 4H2O**

This reaction represents the combustion of propane (C3H8), which produces carbon dioxide (CO2) and water (H2O). In this process, chemical bonds are broken and new bonds are formed, resulting in the formation of different substances, which is characteristic of a chemical change.

The other equations represent physical changes (phase changes) rather than chemical changes.