Question

The osmotic pressure of blood at 37°C is 8.21 atm. How much glucose in grams should be used per litre of aqueous solution for an intravenous injection so that it is isotonic with blood? (Molecular wt of glucose = 180 g/mol)

The osmotic pressure of blood at 37°C is 8.21 atm. How much glucose should be used per litre for an intravenous injection so that it is isotonic with blood?

Answer 1

π (osmotic pressure) = 8.21 atm

T = 273 + 37

T = 310 K

Hence π = CRT

where C is molar concentration.

`8.21 = w/M xx 0.082 xx 310`

where M = 180 g/mol

`w = (8.21 xx 180)/(0.082 xx 310)`

`w = 58.13` gm

∴ To prepare a solution isotonic with blood, 58.13 g of glucose per litre of solution is required.