A sample of an ionic compound containing iron and chlorine is analyzed and found to have a molar mass of 126.8 g/mol. what is the charge of the iron in this compound?

Answer is: the charge of the iron in this compound is + 2.

Atomic mass of iron is 55,8 g/mol.

Atomic mass of chlorine is 35,5 g/mol.

If compound is FeCl, molar mass would be 55,8 g/mol + 35,5 g/mol = 91,3 g/mo, that is not correct.

If compound is FeCl₂, malar mass of compound would be:

55,8 g/mol + 2·35,5 g/mol = 126,8 g/mol, that is correct.

Oxaidation number of chlorine is - 1.