Question

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?

Answer 1

Answer: 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:

$n_1M_1V_1=n_2M_2V_2$

where,

$n_1,M_1\text{ and }V_1$ are the n-factor, molarity and volume of acid which is $H_3PO_4$

$n_2,M_2\text{ and }V_2$ are the n-factor, molarity and volume of base which is $KOH$

We are given:

$n_1=3\\M_1=0.656M\\V_1=40mL\\n_2=1\\M_2=0.15M\\V_2=?mL$

Putting values in above equation, we get:

$3\times 0.656\times 40=1\times 0.15\times V_2\\\\V_2=542.8mL$

Hence, the volume of KOH solution required is 542.8 mL