mols base = M x L = ?
If citric acid, then mols citric acid = 1/3 mols NaOH.
If tartaric acid, then mols tartaric acid = 1/2 mols NaOH.
mols = grams/molar mass or
molar mass = grams/mols.
If citric acid then molar mass = 0.956/mols citric acid from above.
If tartaric acid then molar mass = 0.956/mols tartaric acid from above.
Look up or calculate the molar mass of both tartaric acid and citric acid and compare with the molar mass of the unknown you calculated.
An unknown solid acid is either citric acid or tartaric acid. To determine which acid you have, you titrate a sample of the solid with NaOH. The appropriate reactions are as follows:
Citric acid:
H3C6H5O7 (aq) + 3NaOH (aq) -> 3H2O (l) + Na3C6H5O7 (aq)
Tartaric acid:
H2C4H4O6 (aq) + 2 NaOH (aq) -> 2H2O (l) + Na2C4H4O6
A 0.956g sample requires 29.1 mL of 0.513 M NaOH for titration to the equivalence point. What is the identity of the unknown acid?
1 answer
1 answer