How many milliliters of a 0.15--m solution of koh will be reuired to titrate 40.00ml of a 0.656-m solution of h3po4?
h3po4 + 2koh ? k2hpo4 + 2h2o

The volume of HBr solution required is 542.8 mL

Explanation:

To calculate the concentration of base, we use the equation given by neutralization reaction:

where,

are the n-factor, molarity and volume of acid which is

are the n-factor, molarity and volume of base which is

We are given:

Putting values in above equation, we get:

Hence, the volume of KOH solution required is 542.8 mL

your answer would be “dry”