Mass of urea,
WB = 5 g
R = 0.0821 L atm K-1 mol-1
T = 273 + 27°C = 300 K
Molecular mass of urea,
MB = 60 g mol-1
V = 100 mL = 0.1L
\(\pi=\frac{W_BRT}{M_B\times V}\)
= \(\frac{5g\times0.0821\,L\,atm\,K^{-1}\,mol^{-1}\times\,300\,K}{60\,g\,mol^{-1}\times\, 0.1\,L}\)
= 20.53 atm