Which equation is a reduction half-reaction that is written correctly?
Zn2+(aq) + e– mc004-1.jpg Zn(s)
Be2+(aq) + 2e– mc004-2.jpg Be(s)
2Cl–(aq) mc004-3.jpg Cl2(g) + 2e–
Au(s) mc004-4.jpg Au3+(aq) + 3e–