Concentration Titration Error

[MDwannabe7]

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In performing standardized titration, a student began by dissolving a certain substance in 50 mL of water. If the actual volume of water added were slightly larger than the measured volume, what effect would this have had on the final determination of the concentration?

The concentration they are looking for is after the titration. Since, in a titration, you use a known volume of a substance on known molarity/normality and titrate with a known volume of a substance of unknown molarity/normality - you can use the equation M1V1 = M2V2 to calculate the molarity/normality of the unknown substance. If you put in the wrong volume initially, wouldn't your titrant be more dilute, thus making the unknown more concentrated?

Why then, is the answer that the calculated concentration would have been the same as the actual concentration?

 

[Lukkie]

adding a small amount of extra water has hardly any effect on the acidity/basicity of the solution. think about Kw: its 10^-14, a tiny number. your number for titration might change by something like 0.0000001mL