Question

If 18.00 mL of 0.1000 M magnesium hydroxide reacts with 10.00 mL of hydrochloric acid, what is the molarity of the acid solution?

Answer 1

0.36M HCl

Step-by-step explanation:

The reaction of Mg(OH)₂ with HCl is:

Mg(OH)₂ + 2HCl → MgCl₂ + 2H₂O

Where 1 mole of magnesium hydroxide reacts with 2 moles of HCl

To solve this question, we need to find the moles of Mg(OH)₂ that reacted and, with chemical equation, solve for the moles of HCl and its molarity (Using the 10.00mL = 0.01000L) as follows:

Moles of Mg(OH)₂:

18mL = 0.018L * (0.100mol / L) = 0.0018 moles Mg(OH)₂

Moles HCl:

0.0018 moles Mg(OH)₂ * (2 moles HCl / mol Mg(OH)₂) = 0.0036 moles HCl

Molarity HCl:

0.0036 moles HCl / 0.0100L =

0.36M HCl