Question

Of the following measurements the one most suitable for the determination of the molecular weight of Oxyhaemoglobin, a molecule with a molecular weight of many thousand, is:

• A. the vapour pressure lowering
• B. the elevation of the boiling point
• C. the depression of the freezing point
• D. the osmotic pressure

Answer 1

The correct option is D the osmotic pressure

To determine the molecular weight of oxyhemoglobin, the solution would have an osmotic pressure of around 19 mm of Hg.

Since the M.W is in thousands, as the solution would have a molarity of 1/1000.

Thus, to predict the molecular weight, osmotic pressure would be the most suitable for molecules with low solubility in water.