An analytical chemist ways out, 0.314 g of an unknown diprotic acid into a 250 mL volumetric flask and I lose to the mark with distilled water. She then titrates the solution with 0.0900 M NaOH solution. When the titration reaches the equivalence point the chemist fine she has added 52.0 mL of NaOH solution calculate the molar mass of the unknown acid round your answer to three significant digits.
To calculate the molar mass of the unknown acid, we need to use the information given and perform some calculations.
1. Determine the number of moles of NaOH used:
moles of NaOH = volume of NaOH (in L) * concentration of NaOH (in M)
moles of NaOH = 52.0 mL * 0.0900 M / 1000 mL/L = 0.00468 mol
2. Determine the number of moles of the unknown acid:
Since the acid is diprotic, it can react with two moles of NaOH per mole of acid.
moles of acid = 0.5 * moles of NaOH
moles of acid = 0.5 * 0.00468 mol = 0.00234 mol
3. Calculate the molar mass of the unknown acid:
molar mass = mass (in g) / moles
molar mass = 0.314 g / 0.00234 mol = 134 g/mol
The molar mass of the unknown acid is 134 g/mol (rounded to three significant digits).