Question

How many electrons are in an Fe2+ ion? (1) 24 (3) 28 (2) 26 (4) 56

Answer 1

The answer is (1) 24. There are 26 protons in nucleus of Fe atom. There is 26 electrons in Fe atom. Fe atom loses 2 electrons and change to Fe2+ ion. So there is 24 electrons in Fe2+ ion.

Answer 2

Atomic number of iron = 26 
Number of protons in the neucleus = 26 
Number of electrons in a neutral Fe atom = 26 
Number of electrons in Fe2+ ion = 26 - 2 = 24