Question

What is the number of moles of iron atoms in 19.2 grams of iron (II) oxide?

What is the number of moles of iron atoms in 19.2 grams of iron (II) oxide?

O=16g
Fe=56g

Answer 1

1 molecule of `Fe_2O_3` contains 2 atoms of iron.
Thus, 1 mole of `Fe_2O_3` has `2xxN_A` no. of iron atoms.
Molar mass of `Fe_2O_3` is 160 gm.
Thus,1 gm of this compound has `(2xxN_A)//160` no. of `Fe` atoms.
19.2 gm of `Fe_2O_3` has `(2xxN_Axx19.2)//160` or `1.45xx10^23` no of `Fe` atoms.