Question

A solution is made by dissolving 13.2 g of HCl in 774.7 mL of water. Calculate the pH of the solution. Assume that the volume of the solution not change with the addition of HCl.

Answer 1

Given data,

Mass of HCl = 13.2 g

Volume = 774.7 mL

Moles of HCl = mass / molar mass

= 13.2 g . / 36.46 g / mol

= 0.3620 mol

Molarity of HCl = Moles of solute / Volume of solution( mL ) x 1000 mL

= 0.3620 / 774.7 x 1000

= 0.4672 M

H⁺ = 0.4672 M

We know that,

pH = -log [H⁺]

= -log ( 0.4672 )

= -(- 0.330)

pH = 0.330