A 100.0 ml aqeuous solution that contains 0.50 g of hemoglobin has an osmotic pressure of 0.00178 atm. What is the molar mass of hemoglobin?
pi = MRT
Substitute and solve for M = molarity
Then M = mols/L. You know M and L, solve for mols
Then mols = grams/molar mass. You know grams and mols, solve for molar mass
68724.16
Can u show the steps on how u got that answer ?
To determine the molar mass of hemoglobin, we can use the formula:
Molar mass = (Osmotic pressure × Volume) / (Number of moles of solute)
First, let's calculate the number of moles of solute (hemoglobin) using the provided mass and molar mass formula:
Number of moles = Mass / Molar mass
Given:
Mass of hemoglobin = 0.50 g
Volume of solution = 100.0 ml
Since we need the volume in liters, we convert it:
Volume of solution = 100.0 ml = 100.0 ml / 1000 = 0.100 L
Now, let's calculate the number of moles of hemoglobin:
Number of moles = 0.50 g / Molar mass
Next, we plug in the given osmotic pressure, volume, and calculated number of moles into the molar mass formula:
Molar mass = (0.00178 atm × 0.100 L) / (Number of moles)
Since we've been given the osmotic pressure in atm, the volume in liters, and we're trying to calculate the molar mass in g/mol, we need to rearrange the formula as follows:
Molar mass = (Osmotic pressure × Volume) / (Number of moles)
Substituting the values, we have:
Molar mass = (0.00178 atm × 0.100 L) / (0.50 g / Molar mass)
Simplifying:
Molar mass = (0.000178 L.atm) / (0.50 g / Molar mass)
Now, we can solve for the molar mass by cross-multiplying:
Molar mass × (0.50 g) = (0.000178 L.atm)
Dividing both sides by (0.50 g):
Molar mass = (0.000178 L.atm) / (0.50 g)
Finally, we calculate the value:
Molar mass = 0.000356 g/L.atm
So, the molar mass of hemoglobin is approximately 0.000356 g/L.atm.