For each of the following formulas, write the

name of each element and the number of atoms

of that element that are in the formula.

(a) 2K³PO⁴

(b) 3Al (OH) ³

(c) 5Fe² (SO⁴) ³

(a) Potassium 3; phosphorus 1; oxygen 4

(b) Aluminium 3; oxygen 9; hydrogen 9

(c) Iron 10; sulfur 15; oxygen 60

Explanation:

(a) K₃PO₄

In one formula unit of K₃PO₄, there are three atoms of potassium (K), one atom of phosphorus (P), and four atoms of oxygen (O).

In two formula units there are

Potassium - six atoms

Phosphorus - two atoms

Oxygen - eight atoms

(b) Al (OH) ₃

In one formula unit of Al (OH) ₃, there is one atom of aluminium (Al), three atoms of O, and three atoms of Hydrogen (H).

In three formula units there are

Aluminium - three atoms

Oxygen - nine atoms

Hydrogen - nine atoms

(c) Fe₂ (SO₄) ₃

In one formula unit of Fe₂ (SO₄) ₃, there are two atoms of iron (Fe), three atoms of sulfur (S), and 12 atoms of O.

In five formula units there are

Iron - 10 atoms

Sulfur - 15 atoms

Oxygen - 60 atoms