We have a neutralization between the HCl (acid) and Ba(OH)2 (base):
To calculate the mL asked, we need to use the next formula:
M1 x V1 = M2 x V2 (1)
We assign number 1 to HCl and number 2 to Ba(OH)2
Remember: M molarity and V volume
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Data:
We know M1 = 0.165 M (HCl) and M2 = 0.101 M, V2 = 25.0 mL.
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Procedure:
We clear V1 from (1):
V1 = M2 x V2/M1 = 0.101 M x 25.0 mL/0.165 M = 15.3 mL
Answer: V1 = 15.3 mL
