50.00 mL of unknown calcium hydroxide solution is titrated with 0.250 M standard nitric acid solution. If 43.43 mL of the standard acid solution is required to reach a phenolphthalein endpoint, what is the molarity of the unknown calcium hydroxide solution

Molarity of the unknown calcium hydroxide solution is 0.217 M.

Explanation:

Given: = 50.00 mL,     = ?

= 43.43 mL,         = 0.250 M

Formula used is as follows.

Substitute the values into above formula as follows.

Thus, we can conclude that molarity of the unknown calcium hydroxide solution is 0.217 M.

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