Step 1
In a titration, the next equation is used in the equivalence point:
Where,
Number 1 will the conditions of HBr
Number 2 will the conditions of Ca(OH)2
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Step 2
Information provided:
M1 = 0.0105 M
V1 = unknown
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M2 = 0.0100 M
V2 = 125 mL
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Step 3
Procedure:
From step 1, V1 is found as follows:
Answer: V1 = 119 mL