Osmosis

Exercise 4

    

The main cause of the rising of the sap in the trees is osmosis. If the sap $S$ (mass density $\rho = 1\frac{g}{cm^3}$ is $0.1\frac{mol}{L}$ more concentrated than the liquid surrounding the roots, then calculate by $25^oC$ the height ascent of sap in the tree!

a) $\Pi_{sap}=\Delta [S]RT$ so: $\rho\;g\;h = \Delta [S]RT$ International System of Units (SI): $1000\frac{kg}{m^3}9.8\frac{N}{kg}\;h=100\frac{mol}{m^3}8.3\frac{N\;m}{mol\;K}298\;K$ $h=25.2\;m$