Purification of nickel can be achieved by electrorefining nickel from an impure nickel anode onto a pure nickel cathode in an electrolytic cell. How many hours will it take to plate 18.5 kg of nickel onto the cathode if the current passed through the cell is held constant at 35.5 A

2h2o2--> 2h2o + o2

this reaction is of the spontaneous decomposition of hydrogen peroxide down into water and oxygen.

add 2 molecules of hydrogen peroxide and 2 molecules of water. since oxygen is naturally diatomic, the total number of atoms of each element is now the same on both sides of the equation so it is balanced.

this may not be entirely correct but let me know.

the answer is option a.