If 1.30 grams of a protein (non - electrolyte) are added to a 100.0 mL of water, the osmotic pressure of the resulting solution is 0.0074 atm at 298 K. What is the molar mass of the protein?

M = 0.43 * 10⁵ g/mol

Explanation:

Given dа ta:

Mass of protein = 1.30 g

Volume of water = 100.0 mL (100/1000 = 0.1 L)

Pressure of solution = 0.0074 atm

Temperature = 298 K

Molar mass of protein = ?

Solution:

Formula:

PV = nRT

n = PV / RT

n = 0.0074 atm * 0.1 L / 0.0821 atm. L / mol. K * 298 K

n = 0.00074 / 24.5 / mol

n = 3.0 * 10⁻⁵ mol

Molar mass of protein:

Number of moles = mass / molar mass

3.0 * 10⁻⁵ mol = 1.30 g / M

M = 1.30 g / 3.0 * 10⁻⁵ mol

M = 0.43 * 10⁵ g/mol