Question

Determine the reaction type for this chemical equation:

Zn + 2HCl → ZnCl2 + H2

Group of answer choices

decomposition

combustion

double replacement

synthesis

Answer 1

This is a single replacement (single displacement) reaction: Zn atoms displace H+ from HCl to give Zn2+ (as ZnCl2) and H2.

Zn → Zn2+ + 2e− and 2H+ + 2e− → H2 (redox). None of the four choices listed (decomposition, combustion, double replacement, synthesis) correctly names this type.