Topic(s): Redox Reactions Which equation represents a redox reaction? AgNO_(3)+NaClarrow AgCl+NaNO_(3) PCl_(5)+4H_(2)Oarrow H_(3)PO_(4)+5HCl 3Fe+4H_(2)Oarrow Fe_(3)O_(4)+4H_(2) MgCO_(3)+2HClarrow MgCl_(2)+CO_(2)+H_(2)O

The equation that represents a redox reaction is:<br /><br />$3Fe+4H_{2}O\rightarrow Fe_{3}O_{4}+4H_{2}$<br /><br />In this reaction, iron (Fe) is oxidized from 0 to +8 oxidation state, while hydrogen (H) is reduced from +1 to 0 oxidation state. This change in oxidation states indicates that it is a redox reaction.