Given, number of molecules of urea =6.02×1020 ∴ Number of moles =NA6.02×1020=6.02×10236.02×1020=1×10−3 mol Volume of the solution =100 mL=1000100 L=0.1 L Concentration of urea solution ( in molL−1)=0.11×10−3molL−1=1×10−2 mol L−1=0.01 mol L−1