Water molecule is very polar. Polar end of molecule attracts opposite charges on another water molecule (acts like magnet). How will you explain this property of water with reference to upward movement of water? Comment on the upward movement of water given the intermolecular hydrogen bonding in water.

The process by which water molecules remain attached to one another via hydrogen bonding in between them is known as cohesion of the water molecules. The water column that moves upwards via the xylem vessels from the root to the leaves due to the transpiration pull does not break due to this property's contribution along with the contribution of the property of adhesion. The cohesion is responsible for providing tensile strength which aids in the pulling of the water from the roots to the tips of the leaves. The upward movement of water is via the xylem vessels where it is facilitated by three forces: adhesion ( where water molecules interact with other molecules like the inner walls of the xylem), cohesion (attachment of water molecules together forming an uninterrupted water column that does not break and does not allow cavitation to occur in xylem vessels) and surface tension.


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