What volume of 0.500 M NaOH is needed to neutralize 45.0 mL of 0.400 M HCl?

1 Answer
May 3, 2016

NaOH(aq)+HCl(aq)NaCl(aq)+H2O(l)

Explanation:

Clearly there is a 1:1 equivalence, and as a first step we calculate the number of moles of hydrochloric acid:

45.0×103L×0.400molL1 = 1.80×102mol hydrochloric acid.

We find an equivalent molar quantity of sodium hydroxide:

1.80×102mol0.500molL1×103mLL1 = 36.0mL.

This volume is reasonable, in that it is LESS than the volume of the less concentrated acid.