Neutrons don’t carry an electrical charge, meaning that adding or subtracting them from the nucleus will not change the electrical charge of the nucleus of an atom. But, adding/removing neutrons changes the mass of the nucleus. This is how isotopes are formed.
ANSWER
36.12 degrees fahrenheit
Fe: 2 x 55.845 = 111.69
O: 3 x 15.9994= 47.9982
111.69 + 47.9982 = 159.69 g/mol
