If a #"62.4 g/L"# solution of bovine insulin in an appropriate solvent achieves an osmotic pressure of #"0.305 atm"# at #"298 K"#, estimate the molar mass?
#a)# #"10000 g/mol"#
#b)# #"5000 g/mol"#
#c)# #"506887 g/mol"#
#d)# #"5069 g/mol"#
1 Answer
Formula Wt Insulin ~ 5000 g/mole*
Explanation:
Using the Osmotic Pressure Equation*
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Note: the method of mole weight analysis is not specified. That is, the 5808 mole wt. value is perhaps a weight average mole weight (mass fraction analysis), whereas the 5000 mole wt. calculation is based upon
The calculation using the osmotic pressure equation is correctly done but is a colligative property dependent relationship which will typically give lower values than other methods defining weight average mole weights.