How many grams of hydrochloric acid can be neutralized by 5g Mg(OH)2?

Question

The equation is Mg(OH)2 + 2HCl -> MgCl2 + 2H2O.

please help! also, can i see how you worked this problem out as well? thanks!

Answer 1

Molecular mass Mg(OH)2 = 58.3 g / mol

5 g / 58.3 = 0.0858 mole

the ratio between Mg(OH)2 and HCl is 1 : 2 so are needed 0.0858 x 2 = 0.171 mole HCl

Molecular mass HCl = 36.46 g / mol

0.171 mole x 36.46 g / mol = 6.23 g HCl

Answer 2

1. work out the Mr of magnesium hydroxide.
2. moles Mg(OH)2 = 5/Mr
3. moles HCl is 2 x this value
4. now multiply by 36.5