Question

How many moles of `(NH_4)_2SO_4` are present in 25.0 grams of `(NH_4)_2SO_4`?

Answer 1

0.2 moles

Explanation:

Mass of one mole of Ammonium Sulfate is 132 g

We can set up conversion factors/ ratios

1 mol Ammonium Sulfate = 132g of `(N`H4`)_2`S`O_4`

1 mol Ammonium Sulfate / 132g of `(N`H4`)_2`S`O_4` (a)

and

132g of `(N`H4`)_2`S`O_4` / 1 mol of Ammonium Sulfate (b)

Using the conversion factor (a) we can find number of moles.

25 g `(N`H4`)_2`S`O_4` x 1 mol of Ammonium sulfate / 132g of `(N`H4`)_2`S`O_4`

0.2 moles Ammonium sulfate