By titration, 26.7 mL of aqueous H2SO4 neutralized
26.2 mL of 0.028 M LiOH solution.
What was the molarity of the aqueous acid
solution?
2LiOH + H2SO4 ==> Li2SO4 + 2H2O
mols LiOH = M x L = ?
Using the coefficients to convert mols LiOH to mols H2SO4.
Now M H2SO4 = mols H2SO4/L H2SO4
To find the molarity of the aqueous acid solution, we can use the equation:
M(acid) * V(acid) = M(base) * V(base)
Where:
M(acid) = molarity of the acid solution
M(base) = molarity of the base solution (LiOH)
V(acid) = volume of the acid solution in liters
V(base) = volume of the base solution in liters
Given:
V(acid) = 26.7 mL = 26.7/1000 = 0.0267 L
V(base) = 26.2 mL = 26.2/1000 = 0.0262 L
M(base) = 0.028 M
Substituting the given values into the equation, we have:
M(acid) * 0.0267 = 0.028 * 0.0262
Solving for M(acid):
M(acid) = (0.028 * 0.0262) / 0.0267
M(acid) = 0.027144
Therefore, the molarity of the aqueous acid solution is approximately 0.027 M.
To solve this problem, we need to use the concept of neutralization and the equation of acid-base reactions.
The balanced chemical equation for the neutralization reaction between H2SO4 (sulfuric acid) and LiOH (lithium hydroxide) is as follows:
H2SO4 + 2LiOH → Li2SO4 + 2H2O
From the balanced equation, we can see that one mole of H2SO4 reacts with two moles of LiOH. Therefore, the mole ratio between H2SO4 and LiOH is 1:2.
Given that 26.7 mL of H2SO4 neutralized 26.2 mL of 0.028 M LiOH solution, we can determine the number of moles of LiOH:
moles of LiOH = volume (L) × concentration (M)
= 26.2 mL × 0.028 M / 1000 mL/L
= 0.0007336 moles
Since the mole ratio between H2SO4 and LiOH is 1:2, the number of moles of H2SO4 can be calculated as follows:
moles of H2SO4 = 0.0007336 moles × (1 mole H2SO4 / 2 moles LiOH)
= 0.0003668 moles
Now, we need to convert the volume of H2SO4 to liters:
volume of H2SO4 = 26.7 mL × 1 L / 1000 mL
= 0.0267 L
Finally, we can determine the molarity (M) of the aqueous H2SO4 solution:
Molarity (M) = moles / volume (L)
= 0.0003668 moles / 0.0267 L
≈ 0.0137 M
Therefore, the molarity of the aqueous H2SO4 solution is approximately 0.0137 M.