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1 year ago

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A protein subunit from an enzyme is part of a research study and needs to be characterized. A total of 0.155 g of this subunit w

as dissolved in enough water to produce 2.00 mL of solution. At 28 ∘C the osmotic pressure produced by the solution was 0.138 atm. What is the molar mass of the protein?

1 answer:

olga_2 [115]1 year ago

6 0

Answer : The molar mass of protein is, $1.38\times 10^4g/mol$

Explanation :

Formula used :

$\pi =CRT\\\\\pi=\frac{w\times 1000}{M\times V}RT$

where,

$\pi$ = osmotic pressure = 0.138 atm

C = concentration

R = solution constant = 0.0821 L.atm/mol.K

T = temperature = $28^oC=273+28=301K$

w = mass of protein subunit = 0.155 g

M = molar mass of protein subunit = ?

V = volume of solution = 2.00 mL

Now put all the given values in the above formula, we get:

$\pi=\frac{w\times 1000}{M\times V}RT$

$0.138atm=\frac{0.155g\times 1000}{M\times 2.00ml}\times (0.0821L.atm/mole.K)\times (301K)$

$M=13878.17g/mol=1.38\times 10^4g/mol$

Therefore, the molar mass of protein is, $1.38\times 10^4g/mol$

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$\Delta G^o$ = standard Gibbs free energy = -5.980 kJ/mol = -5980 J/mol

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Rules for the balanced chemical equation in basic solution are :

First we have to write into the two half-reactions.

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Now balance the hydrogen and oxygen atoms on both the sides of the reaction.

If the oxygen atoms are not balanced on both the sides then adding water molecules at that side where the more number of oxygen are present.

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Now balance the charge.

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Now balance the charge.

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I hope it helps!

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2 years ago