chemical energy is converted to electrical energy with spontaneous redox reaction Voltage consists of oxidizing agent in one compartment that pulls electrons through a wire from a reducing agent entropy of an isolated system is never decreasing, only if it is in a 2 or more system delta G = delta H - (T * delta S) gibbs free energy = enthalpy - (temperature times entropy) *note T is in kelvin, not Celsius Ecell = E (cathode) - E (anode) IMPORTANT: if the reaction gets reversed (in order to balance, sometimes it will need to be reversed), the sign of the Ecell must switch, however if it gets multiplied (in order to balance) IT REMAINS THE SAME!!

charging = non-spontaneous using = spontaneous G = negative = k>1 G = positive = k<1 k is close to 1, G is close to zero k is far from 1, G is far from zero thermodynamically unfavorable reduction happens, gaining electrons

V = IR voltage = current (amps) * resistance (ohms) y + z --> Y+ + Z- (G<0) degrees of freedom of a molecule in an isolated system energy can neither be created or destroyed; only transferred or converted, meaning E lost = negative E gained

1 joule of work / coulomb of charge transferred J/C = units entropy of an isolated system is never decreasing, only if it is in a 2 or more system as temperature goes to zero, entropy approaches a constant value charging = non-spontaneous using = spontaneous

galvanic cell vs electrolytic cell overall cell reaction is H > 0 and S > 0 entropy