<u>Answer:</u> The identity of the unknown acid is butanoic acid or ascorbic acid.
<u>Explanation:</u>
To calculate the number of moles for given molarity, we use the equation:
Molarity of NaOH solution = 0.570 M
Volume of solution = 39.55 mL
Putting values in above equation, we get:
The chemical equation for the reaction of NaOH and monoprotic acid follows:
By Stoichiometry of the reaction:
1 mole of NaOH reacts with 1 mole of HX
So, moles of monoprotic acid = 0.0225 moles
The chemical equation for the reaction of NaOH and diprotic acid follows:
By Stoichiometry of the reaction:
2 moles of NaOH reacts with 1 mole of diprotic acid
So, moles of diprotic acid =
To calculate the number of moles, we use the equation:
- <u>For butanoic acid:</u>
Mass of butanoic acid = 2.002 g
Molar mass of butanoic acid = 88 g/mol
Putting values in above equation, we get:
- <u>For L-tartaric acid:</u>
Mass of L-tartaric acid = 2.002 g
Molar mass of L-tartaric acid = 150 g/mol
Putting values in above equation, we get:
- <u>For ascorbic acid:</u>
Mass of ascorbic acid = 2.002 g
Molar mass of ascorbic acid = 176 g/mol
Putting values in above equation, we get:
As, the number of moles of butanoic acid and ascorbic acid is equal to the number of moles of acid getting neutralized.
Hence, the identity of the unknown acid is butanoic acid or ascorbic acid.