In: Chemistry
Which describes a property of water that allow plants to transfer it from their roots to their leaves
The plants have internal tubes called xylem that facilitate this
process. Inside the xylem, there is water. This water stretches
directly from the roots to the leaves. When the water molecules are
at the leaves, they evaporate, leaving the plant. Since these
evaporated molecules of water were previously in the chain of water
molecules, they pull the whole chain of water molecules up the
xylem, from the roots to the leaves. This chain continually pulls
water through the plant, as when a molecule is evaporated, the
whole chain moves up a molecule, pulling each consecutive molecule
up a space.
This chain is possible, because water is polar. The electronegative
force of the oxygen is much greater than that of the two hydrogen
atoms, thus hydrogen atoms bond with other oxygen atoms in an
attempt to fulfill the oxygens force.
This is called cohesion - the ability of a substance to bond to
itself. This allows each water molecule in the plant's xylem to
bond to other molecules, pulling the chain up and up as water
evaporates from the top of the plant, in its leaves.