# A titration involves titrating 0.4 M NaOH into a solution of 0.2 M H3PO4. a. Calculate the volume...

## Question:

A titration involves titrating 0.4 M NaOH into a solution of 0.2 M H{eq}_3 {/eq}PO{eq}_4 {/eq}.

a. Calculate the volume of NaOH that will be required to reach the first equivalence point.

b. Calculate the volume of NaOH required to reach the second equivalence point.

Other information: 10 mL H{eq}_3 {/eq}PO{eq}_4 {/eq} was added to 250 mL of deionized water, and the solution was then titrated with NaOH.

## Equivalence Point

The equivalence point the point in a titration where an equivalent amount of the standard solution and unknown solution are present. For an acid-base reaction, an equivalent would be the amount required to neutralize one acidic proton. For a monprotic acid which only has one acidic proton the equivalence point is the end point. However, for polyprotic acids the number of acidic protons is greater than one. Therefore there are multiple equivalence points that correspond to the neutralization of each proton and the end point comes only after all the acidic protons have been neutralized.