Question

Haemoglobin is a chemical in blood that is responsible for transporting oxygen from the lungs to other parts of the body a solution containig 1g of Haemoglobin in 1000cm³ of water had an osmotic preasure of 365N/m² at 298k estimate the molar mass of the Heamoglobin

Answer 1

$$\pi = MRT$$

$\pi = 365 Pa = 365 Pa\times \frac{1 atm}{101325 Pa} =0.003602 atm$

$M = \frac{n}{V} = \frac{moles}{1 L}$

$R = 0.0821\frac{L\times atm}{mol \times K}$

$T = 298 K$

$$0.003602 atm = \frac{n}{1L} \times 0.0821 \frac{L\times atm}{mol \times K} \times 298 K$$

$$n = 1.47\times 10^{-4} moles$$

$m = M\times n$

$$\therefore M = \frac{m}{n} = \frac{1 g}{1.47\times 10^{-4}} = 6792 \frac{g}{mol} =6790 \frac{g}{mol}$$

Answer: $6790 \frac{g}{mol}$