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mimocs
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Myoglobin is a globular protein, with molar mass m ≈ 17,000g/mole. The buoyant correction typically reduces m to m' ≈ 0.25m. Calculate the concentration ratio of the protein at the top of a 4 cm test tube and that at the bottom.
Here, m' stands for effective mass.
I tried as below.
I used the equation of buyoancy so that the effective mass reduce into 0.25m.
m'g = (ρ-ρ')Vg = 0.25mg = 0.25ρVg
(ρ is the density of myoglobin, and ρ' is the density of water)
→ 0.75ρ = ρ'
So since ρ > ρ', I think the myoglobin should sink to the bottom of the test tube.
As a result, the concentration of myoglobin at the top is 0 and let the concentration of the bottom is M.
Then, concentration ratio of bottom and the top becomes 0 / M which gives me 0.
However, I don't think my answer is reasonable.
Why does the problem give me the molar mass?
I hope anyone could ever help me.
Here, m' stands for effective mass.
I tried as below.
I used the equation of buyoancy so that the effective mass reduce into 0.25m.
m'g = (ρ-ρ')Vg = 0.25mg = 0.25ρVg
(ρ is the density of myoglobin, and ρ' is the density of water)
→ 0.75ρ = ρ'
So since ρ > ρ', I think the myoglobin should sink to the bottom of the test tube.
As a result, the concentration of myoglobin at the top is 0 and let the concentration of the bottom is M.
Then, concentration ratio of bottom and the top becomes 0 / M which gives me 0.
However, I don't think my answer is reasonable.
Why does the problem give me the molar mass?
I hope anyone could ever help me.