Properties of Water - AP Bio

Polarity

Polar covalent bonds created by unequal sharing of electrons between oxygen and hydrogen within the molecule of water.

Cohesion

Attraction of molecules for other molecules of the same kind (water to water)

Adhesion

The attraction to other molecules that are polar or have charge (water to other molecules)

Capillary action

the upward movement of water due to the forces of cohesion , adhesion, and surface tension. - occurs when adhesion is greater than cohesion

High specific heat

Water resists changes in temperature - How? Hydrogen bonds (heat is released when hydrogen bonds form)

High heat of vaporization

WAter requires a large amount of energy to evaporate due to strong hydrogen bonds

Evaporative cooling

As water molecules evaporate, the surface they evaporate from gets cooler - super important because it moderates earth´s climate, think sweating in humans.

Density (floating ice)

As water solidifies it expands and becomes less dense because of hydrogen bonds

Solvent

Dissolving agent in a solution (water)

solute

Substance that is dissolved

Like dissolves like

WAter will form hydrogen bonds with the sugar or protein to dissolve it

pH

a measure of how acidic or basic a solution is

acidic

substance that releases hydrogen ions when dissolved in water

basic

a substance that accepts hydrogen or releases hydroxide ionsb

buffer

a solution that resists changes in pH when an acid or base is added - helps maintain pH stability in biological systems.

cohesion allows for

transport of water and nutrients up a xylem of the leaf

adhesion in plants…

this allows water to cling to the cell walls to resist the downward pull of gravity