How liters of 1.5 M #HCl# solution would react completely with 25 moles #Ca(OH)_2#?

1 Answer


Just over 33 litres


First write the balanced equation:

#Ca(OH)_2 (s) + 2HCl (aq) -> CaCl_2 (aq) + 2H_2 O (l)#

From this you can see that each mole of calcium hydroxide reacts with 2 moles of hydrochloric acid.

You have 25 moles of calcium hydroxide, so it means that 50 moles of hydrochloric acid is required.

The molarity of the hydrochloric acid is 1.5 M, and

#"number of litres" = "number of moles"/"molarity"#

This is

#"50 moles"/"1.5 mol/L" = "33.3 litres"#