20cm3 of sodium hydroxide solution containing 8.0g/dm3 were required for complete

Question

neutralization of 0.18g of a dibasic acid H2X. Determine the R.M.M of the acid.

Answer 1

First, calculate the number of moles of sodium hydroxide used in the neutralization reaction:

Number of moles of NaOH = 20 cm3 x 8.0 g/dm3 / 1000 = 0.16 moles

Since the acid is dibasic, it will require twice the number of moles of sodium hydroxide for complete neutralization:

Number of moles of H2X = 0.16 x 2 = 0.32 moles

Finally, calculate the relative molecular mass (R.M.M) of the acid H2X:

R.M.M = Mass / Moles
Mass = 0.18g
Moles = 0.32 moles

R.M.M = 0.18g / 0.32 = 0.5625 g/mol

Therefore, the relative molecular mass of the acid H2X is 0.5625 g/mol.