Final answer:
The molar mass of the unknown diprotic acid is 139 g/mol.
Step-by-step explanation:
To calculate the molar mass of the unknown diprotic acid, we need to use the concept of titration. In this case, we have 0.119 g of the acid being titrated with 16.0 mL of a 0.107 M NaOH solution. We can start by calculating the number of moles of NaOH used:
moles of NaOH = volume of NaOH (L) * molarity of NaOH (mol/L)
moles of NaOH = 0.0160 L * 0.107 mol/L = 0.001712 mol NaOH
Since the acid is diprotic, we know that 1 mole of acid reacts with 2 moles of NaOH. Therefore, the number of moles of the acid will be half the number of moles of NaOH used:
moles of acid = 0.001712 mol NaOH / 2 = 0.000856 mol acid
To find the molar mass of the acid, we can divide the mass of the acid by the number of moles:
molar mass of acid = mass of acid (g) / moles of acid
molar mass of acid = 0.119 g / 0.000856 mol
molar mass of acid = 139 g/mol