Practice: Cu2+ is reduced to Cu(s) at an electrode. If a current of 1.25 A is passed for 72 hours, what mass of copper is deposited at the electrode? (MW of Cu: 63.55 g/mol)
Electroplating involves coating an electrode through the use of current
Concept #1: Electrical current (A) is the rate at which electrons move from electrode to electrode.
Example #1: Determine the electrical current produced if a charge 4.14 x 103 C passes through a wire for 15 mins.
Concept #2: Electrochemical Stoichiometry deals with calculations in electrochemical cells that involve current and charge.
Example #2: Gold can be plated out of a solution containing Au3+ based on the following half reaction:
Au3+ (aq) + 3 e– →. Au (s)
What mass of gold is plated by a 41 minute flow of 6.8 A current?
Concept #3: When the initial mass for a half reaction is given we can utilize the mass version of the stoichiometric chart to find time.
Example #3: How much time (in hours) would it take to plate out 42.1 g nickel using a current of 3.08 A?
Ni2+ (aq) + 2 e– →. Ni (s)
Practice: Cu2+ is reduced to Cu(s) at an electrode. If a current of 1.25 A is passed for 72 hours, what mass of copper is deposited at the electrode? (MW of Cu: 63.55 g/mol)
Practice: A solution of Mn+5 is used to plate out Mn in an electrochemical cell. If a total of 1.13 g of Mn is plated out in a total time of 1600 seconds, what was the electrical current used? (MW of Mn is 54.94 g/mol)
