a) What is metal corrosion? Check the appropriate options below. Several of the statements may be correct.

i. Corrosion of metal by the metal emitting electrons

ii. A process that requires an anode, a cathode and an electrolyte that can transport charges

iii. Corrosion of metal by the metal absorbing electrons

iiii. An acid / base reaction

b) Which of the following options will prevent corrosion of an iron nail in water? Only one answer is correct.

i. We attach a piece of metal zinc to the nail

ii. We fasten a copper wire around the nail

iii. We add HCl to the water (acidic solution)

iiii. We saturate the water with oxygen gas