Question

What is the molar concentration of a solution of LiOH if 65 ml are titrated to an endpoint by 175 ml of a solution of HBr that is 0.025 M?

a. 0.065 M
b. 0.025 M
c. 0.130 M
d. 0.175 M

Answer 1

The molar concentration of the LiOH solution is 0.004375 M.

Step-by-step explanation:

To find the molar concentration of a solution of LiOH, we can use the balanced chemical equation between LiOH and HBr:

LiOH + HBr → LiBr + H₂O

We can first calculate the number of moles of HBr using its molarity and volume:

# moles HBr = (0.025 M)(0.175 L) = 0.004375 mol HBr

Since the stoichiometry of the balanced equation tells us that the ratio of moles of HBr to moles of LiOH is 1:1, the molar concentration of the LiOH solution would also be 0.004375 M.