Question

Part A When titrated with a 0.1038 M solution of sodium hydroxide, a 52.00 mL solution of an unknown polyprotic acid required 22.86 mL to reach the first equivalence point. Calculate the molar concentration of the unknown acid. VALDO ? Submit Request Answer

Answer 1

Balanced chemical equation is:

NaOH + HnA ---> NaHn-1A + H2O

Here:

M(NaOH)=0.1038 M

V(NaOH)=22.86 mL

V(HnA)=52.0 mL

According to balanced reaction:

1*number of mol of NaOH =1*number of mol of HnA

1*M(NaOH)*V(NaOH) =1*M(HnA)*V(HnA)

1*0.1038*22.86 = 1*M(HnA)*52.0

M(HnA) = 0.04563 M

Answer: 0.04563 M