A 0.105g sample of a diprotic acid of unknown molar mass is dissolved in water and titrated with 0.1288 M NaOH. The endpoint is reached after adding 15.2 mL of base.
What is the molar mass of the unknown acid?
What is the molar mass of the unknown acid?
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Calculate moles of NaOH used: 0.0152 L X 0.1288 mol/L = 1.96 X 10^-3 mol NaOH. Since the acid is diprotic, the 1.96 X 10^-3 moles of NaOH = 2 moles of acid. So, the moles of acid in the sample is 9.79 X 10^-4 moles
To calculate its molar mass, divide the mass of the sample by the moles of acid:
0.105 g / 9.79 X 10^-4 mol = 107 g/mol
To calculate its molar mass, divide the mass of the sample by the moles of acid:
0.105 g / 9.79 X 10^-4 mol = 107 g/mol