Insulin `(C_2H_(10)O_(5))_n,` is dissolved in a suitable solvent and the osmotic pressure `(pi)` of solutions of various concentrations (g/cc) C is measured at `20^@C.` The slope of the plot of t against 'C' is found to be `4.65 xx 10^(-3)`. The molecular weight of insulin is:

Options

A. `4.8xx 10^(5)`
B. `9xx 10^(5)`
C. `3 xx 10^(5)`
D. `5.17xx 10^(6)`

Answer

D

Explanation

`pi V= (w_(B))/(m_(B)) xx RT, pi = ((w_(B))/(V)) (RT)/(m_(B))`
`pi = C xx (RT)/(m_(B)) xx 1000` ..(i)
where C= concentration in g//cc, `y= x xx m` …(ii)
Comparing eqs (i) and (ii), Slope `=(RT)/(m_(B))xx 1000`
`m_(B)= (RT)/("Slope") xx 1000= (0.0821 xx 293 xx 1000)/(4.65 xx 10^(-3))=5.17 xx 10^(6)`