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Answer the following.
During an experiment, a scientist tried to determine the molecular mass of a protein by applying…
During an experiment, a scientist tried to determine the molecular mass of a protein by applying elevation of boiling point method but did not succeed. When she used osmotic pressure method, she found that $20\text{ g}$ of protein in $2$ litres solution had an osmotic pressure of $0\cdot0171\text{ atm}$ at $25^\circ\text{C}$.
Based on the findings of the scientist, calculate the molecular mass of protein.
($R = 0\cdot0821\text{ dm}^3\text{ atm K}^{-1}\text{mol}^{-1}$)
Answer
Answer
AIFormula used: Osmotic pressure: pi = i*C*R*T with R = 0.0821 L atm K^-1 mol^-1, T = 298 K, V = 2 L, i = 1, pi = 0.0171 atm, w2 = 20 g, so M2 = 14307 g mol^-1
$\pi = \frac{w_2 R T}{M_2 V}$, so $M_2 = \frac{w_2 R T}{\pi V}$
$T = 25 + 273 = 298\text{ K}$
$M_2 = \frac{20 \times 0.0821 \times 298}{0.0171 \times 2} = 14307\text{ g mol}^{-1}$
Final answer: 14307 g mol^-1
From ISC 2026 Improvement Chemistry Paper 1, question 3(i).
Check your working with the Molar mass calculator: molar mass of any formula, hydrates too, with the working and percentage composition.
Check your working with the Chemistry numericals calculator: solutions, electrochemistry and kinetics formulas: fill in what you know and get the rest.