Question

By titration, 24.9 mL of aqueous H2SO4 neutralized 20.5 mL of 0.0365 M LiOH solution.

What was the molarity of the aqueous acid
solution?

Answer 1

Molarity = 0.014 M

Step-by-step explanation:

Given data:

Volume of H₂SO₄ = 24.9 mL

Molarity of H₂SO₄ = ?

Volume of LiOH = 20.5 mL

Molarity of LiOH = 0.0365 M

Solution:

Volume of LiOH:

20.5 mL × 1 L /1000 mL

0.0205L

Volume of H₂SO₄:

24.9 mL × 1 L /1000 mL

0.0249 L

Chemical equation:

H₂SO₄ + 2LiOH → Li₂SO₄ + 2H₂O

Number of moles of LiOH:

Molarity = number of moles / volume in L

0.0365 M = number of moles / 0.0205L

n = 0.0365 M × 0.0205L

n = 0.0365 mol/L × 0.0205L

n = 0.0007 mol

now we will compare the moles of LiOH and H₂SO₄

LiOH : H₂SO₄

2 : 1

0.0007 : 1/2×0.0007 = 0.00035 mol

Molarity of H₂SO₄:

Molarity = number of moles / volume in L

Molarity = 0.00035 mol / 0.0249 L

Molarity = 0.014 M