Unit 1: Chemistry of Life

Oxygen is more electronegative than hydrogen, so shared electrons sit closer to O, giving O a partial negative charge and each H a partial positive charge; the bent shape keeps these charges from canceling.

A weak attraction between the partially positive hydrogen of one water molecule and the partially negative oxygen of a neighboring molecule.

Up to four: two through its hydrogens and two through the lone pairs on its oxygen.

Cohesion is water sticking to water via hydrogen bonds; adhesion is water sticking to other polar or charged surfaces.

Transpiration pulls water from leaves; cohesion keeps the water column continuous while adhesion to xylem walls resists gravity, producing capillary action.

High surface tension, caused by cohesive hydrogen bonding among surface water molecules.