How many moles of hydrogen , H2(g), were collected in the gas-collecting tube?

Wow that a lot of text for my tiny so i no wanna answer

Ithink iit might be

The answer will be c

Remember that rust prevented by placing a sacrificial electrode in electrical contact with the iron. the sacrificial electrode must be composed of a metal that  oxidizes  more easily than iron (that is, it must be below iron in table 18.1).