What is the formula mass of ammonium sulphate?

[Given atomic masses: H= 1 u, N = 14 u, O = 16 u, S = 32 u]

• Ammonium sulphate, whose chemical formula (NH₄)₂SO₄ is an inorganic salt that has several industrial applications. The most typical usage is as a fertilizer for the soil. It has 24% sulphur and 21% nitrogen. 

The formula mass of ammonium sulphate:

•  (NH₄)₂SO₄   = Atomic mass of 2 nitrogen atoms + Atomic masses of 8 hydrogen atoms + Atomic mass of 1 sulphur atom +  Atomic masses of 4 oxygen atoms
  $\Rightarrow$ $2 \times 14 + 8 \times 1 + 1 \times 32 + 4 \times 16$ $\Rightarrow$ $28 + 8 + 32 + 64$
  $\Rightarrow$ 132 u 
• Thus, the formula mass of ammonium sulphate (NH₄)₂SO₄ is 132 u.