Question

A chemistry student needs to standardize a fresh solution of sodium hydroxide. She carefully weighs out 338.mg of oxalic acid H2C2O4 , a diprotic acid that can be purchased inexpensively in high purity, and dissolves it in 250.mL of distilled water. The student then titrates the oxalic acid solution with her sodium hydroxide solution. When the titration reaches the equivalence point, the student finds she has used 136.3mL of sodium hydroxide solution. Calculate the molarity of the student's sodium hydroxide solution. Be sure your answer has the correct number of significant digits.

Answer 1

338.mg=0.3380g of H2C2O4

0.3380g of H2C2O4*(mole/90.03g)= moles of Acid

Moles of acid/0.25L=M

C=(M*0.25L)/0.1363L

Answer 2

Check the wording of your question, and make sure you use the correct number of Sig figs, which should be three.

Answer 3

No.