Insulin, (C_(2)H_(10)O_(5))_(n) is dissolved in a suitable solvent and the osmotic pressure (pi) of solutions of various cocentrations ("g cm"^(-3)) is measured at 20^(@)C. The slope of the plot of pi against C is found to be 4.65xx10^(-3). Calculate the molecular mass of insulin.

Insulin, (C_(2)H_(10)O_(5))_(n) is dissolved in a suitable solvent and

1.	Insulin, (C_(2)H_(10)O_(5))_(n) is dissolved in a suitable solvent and the osmotic pressure (pi) of solutions of various cocentrations ("g cm"^(-3)) is measured at 20^(@)C. The slope of the plot of pi against C is found to be 4.65xx10^(-3). Calculate the molecular mass of insulin.
Answer» Solution :`pi="CRT where C = MOLAR conc. "("mol L"^(-1))` Given values of C (say C') are in `"g cm"^(-3)`. To CONVERT then into `"mol L"^(-1),` we have `C=(C')/(M_(2))xx1000` `therefore""pi=(1000C')/(M_(2))xxRT.` It is like `y=mx` Hence, plot of `pi " vs " C'` will be LINEAR with slope `=(1000RT)/(M_(2))` `therefore(1000RT)/(M_(2))=4.65xx10^(-3)"or"M_(2)=(1000RT)/(4.65xx10^(-3))=(1000xx0.0821xx293)/(4.65xx10^(-3))=5.17xx10^(6)`