Indicate the number of equivalents in each of the following:

Question

4mol Mg2+
0.1mol H+
2mol Cl-
3mol Fe3+

Answer 1

4 mol Mg^2+ = 8 equivalents
0.1 mol H+ = 0.1 equivalent
2 mol Cl^- = 2 equivalents
3 mol Fe^3+ = 9 equivalents.

How does this work?
1 mol Mg = 24.3; 4 mols = 97.2 g
1 eq Mg = 24.3/2 = 12.15g. 97.2/12.15 = 8 equivalents. (2 is the valence but this isn't always the equivalent weight of Mg. It depends upon the reaction.)
1 equivalent Fe = 55.85/3 = ?
1 equivalent H = 1/1 = ?

Answer 2

0.7 mole of Mg2+

Answer 3

0.7 mole of Mg2+
0.7 mole x 2 =1.4 Equivalent, then you should round to 1 Equivalent. So the answer is 1 Equivalent! Hope this helps