Answer:
Molar mass for the protein is 2929.03 g/mol
Explanation:
To determine the osmotic pressure (one of the four colligative properties) we apply this formula:
π = M . R . T
π → Pressure
It must be in atm, so let's convert the mmHg to atm
2.88 mmHg . 1 atm / 760 mmHg = 0.00378 atm
T → Absolute T° (K) = T°C + 273 → 25°C + 273 = 298K
R = 0.082 L.atm/mol.K
Let's replace data: 0.00378 atm = M . 0.082 L.atm/mol.K . 298K
0.00378 atm / (0.082 L.atm/mol.K . 298K) = M
1.55×10⁻⁴ mol/L = M
These are the moles of protein that are contained in 1L of solution, but our volume is 50mL. Let's convert it to L
50mL . 1L / 1000 mL = 0.05 L
Now we can determine the moles of protein we used
1.55×10⁻⁴ mol/L . 0.05L = 7.75×10⁻⁶ moles
This moles corresponds to 22.7 mg of mass. Let's convert the mg to g to find out the molar mas mass
22.7 mg . 1g / 1000 mg = 0.0227 g
Molar mass → g/mol → 0.0227 g / 7.75×10⁻⁶ moles = 2929.03 g/mol
