From 120 grams of zinc with hydrochloric acid, 40 grams of salt were released.

From 120 grams of zinc with hydrochloric acid, 40 grams of salt were released. how many percent is it from the theoretically possible?

The reaction between zinc and hydrochloric acid can be written as an equation:

Zn + 2 HCl = ZnCl2 + H2

Let’s calculate the mass of salt released theoretically.

Molar mass of zinc = 65 g / mol; molar mass of zinc chloride = 136 g / mol

Let’s make the proportion:

120 g of zinc corresponds to X g of zinc chloride as

65 g / mol zinc corresponds to 136 g / mol zinc chloride

X = (120 * 136) / 65 = 251 g of zinc chloride will be released theoretically.

Now let’s find the practical percentage of salt yield.

W = 40/251 = 0.159 or 15.9%

Answer: the yield is 15.9% of the theoretical.