Question

Which equation represents a combustion reaction?
Responses

2AgNO3 + H2S→Ag2S + 2NHO3
2 uppercase A lowercase g uppercase N O subscript 3 end subscript plus uppercase H subscript 2 end subscript uppercase S rightwards arrow uppercase A lowercase g subscript 2 end subscript uppercase S plus 2 uppercase N H O subscript 3 end subscript

2Al + N2→2AlN
2 uppercase A lowercase l plus uppercase N subscript 2 end subscript rightwards arrow 2 uppercase A lowercase l uppercase N

2H2O →2H2+O2
2 uppercase H subscript 2 end subscript uppercase O rightwards arrow 2 uppercase H subscript 2 end subscript plus uppercase O subscript 2 end subscript

4Fe + 3O2→2Fe2O3

Answer 1

4Fe + 3O2 → 2Fe2O3

Reason: a combustion reaction involves O2 as a reactant and formation of an oxide (with release of heat/light). The iron + oxygen reaction fits that definition.