Answer :
Answer:
14.35g/mol
Explanation:
Using the osmotic pressure formula we can calculate the concentration of the unknown protein solution as follows:
Π = iMRT
Π = 2.45 torr
Recall:
760torr = 1atm
2.45torr = 2.45/760 = 0.00322atm
i = 1
R = 0.082atm.L/K /mol
T = 25°C = 25 + 273 = 298K
M =?
M = Π / iRT
M = 0.00322 / (1 x 0.082 x 298)
M = 1.318x10^-4M
Using the ideal gas equation (PV = nRT), let us find the number of mole as follows:
V = 10mL = 10/1000 = 0.01L
P = 1atm
T = 25°C = 25 + 273 = 298K
R = 0.082atm.L/K /mol
n =?
PV = nRT
n = PV /RT
n = (1 x 0.01) / (0.082 x 298)
n = 4.09x10^-4mol
Now, we can find the molar mass of the unknown protein as follows:
Mass of unknown protein = 5.87 mg = 5.87x10^-3g
Number of mole of unknown protein = 4.09x10^-4mol
Molar Mass of unknown protein =?
Number of mole = Mass /Molar Mass
Molar Mass = Mass / number of mole of
Molar Mass of unknown protein = 5.87x10^-3/4.09x10^-4 = 14.35g/mol
Answer:
The molar mass of the protein is 4453.7 g/mol
Explanation:
Step 1: data given
Mass of the unknown protein = 5.87 mg = 0.00587 grams
volume = 10 mL
Osmotic pressure = 2.45 torr
Temperature = 25.0 °C
Step 2 = Calculate concentration
π = i*M*R*T
⇒ π = the osmotic pressure = 2.45 torr = 2.45 / 760 atm = 0.003223684 atm
⇒ i = the van't Hoff factor = 1
⇒ M = the concentration =
⇒ R = the gas constant = 0.08206 L*atm/mol*K
⇒T = the temperature = 25.0 °C = 298 K
0.003223684 = 1 * M *0.08206 * 298
M = 0.0001318 M
Step 3: Calculate moles
Moles = molarity *volume
Moles = 0.0001318 M * 0.01 L
Moles = 0.000001318 moles
Step 4: Calculate molar mass
Molar mass = mass / moles
Molar mass = 0.00587 grams / 0.000001318 moles
Molar mass = 4453.7 g/mol
The molar mass of the protein is 4453.7 g/mol