3.1.7-8 Water & Ions

Hydrogen bond

Weak bonds between a slightly positively charged hydrogen atom in one molecule and a slightly negatively charged atom in another molecule.

Dipolar

Having a positive and negative pole as a result of the uneven distribution of electrons within it.

Metabolite

A substance involved in a metabolic reaction.

Solvent

A liquid that other substances dissolve in.

Solute

A substance that has been dissolved in another substance.

Specific heat capacity

The heat energy needed to raise the temperature of 1g of a substance by 1°C.

Latent heat of vaporisation

The heat energy required to change water to water vapour.

Cohesion

The attraction between molecules of the same type e.g. two water molecules.

Adhesion

The attraction between molecules of different type e.g. a water molecule and the wall of the xylem.

Surface tension

The measure of how hard it is to break the surface of a liquid.

Ion

An atom with a positive or negative charge due to losing or gaining electrons.