Question

Find the osmotic pressure of $\dfrac{M}{10}$ urea solution at 27$^\circ$C. (R = 0.0821 litre atm K$^{-1}$ mol$^{-1}$)

Hint:

Always convert temperature to Kelvin when using gas constant $R$.

Answer 1

Step 1: Formula for osmotic pressure.
\[ \pi = C R T \] where, \(C\) = molar concentration = $\dfrac{M}{10} = 0.1 \, mol \, L^{-1}$ 
\(R = 0.0821  L  atm  K^{-1}  mol^{-1}\)
\(T = 27^\circ C = 27 + 273 = 300 \, K\)

Step 2: Substitution.
\[ \pi = 0.1 \times 0.0821 \times 300 \] \[ \pi = 2.463 \, atm \]

Conclusion:
The osmotic pressure of the solution is: \[ \boxed{2.46 \, atm} \]