Heart pacemakers are often powered by lithium-silver chromate "button" batteries. The overall cell reaction is: 2 Li(s) + Ag2CrO4(s) ? Li2CrO4(s) + 2 Ag(s) The overall cell potential is 3.5V. What is the half-cell potential for the follow half reaction? Ag2CrO4(s) + 2e? ? 2 Ag(s) + CrO4-2?(aq)