AP Biology Topic 1.1: Structure of Water and Hydrogen Bonding

Vocabulary flashcards covering key terms and concepts related to the molecular structure of water, polarity, hydrogen bonding, and water's unique physical properties.

Polar Covalent Bonds

Bonds formed by an uneven sharing of electrons, such as the bonds that bind hydrogen atoms to the oxygen atom within a water molecule.

Polar Molecule

A molecule with two opposite ends featuring slight charges, such as water where the hydrogen side has a slight positive charge and the oxygen side has a slight negative charge.

Hydrogen Bonds

Intermolecular forces formed when the slightly positive side of one polar molecule attracts the slightly negative side of another polar molecule.

High Specific Heat Capacity

A property of water meaning it takes a large amount of energy to raise its temperature because hydrogen bonds resist the kinetic movement of the molecules.

High Heat of Vaporization

A property of water where a substantial amount of heat energy is required to transform liquid water into a gas, occurring at

Evaporative Cooling

A process in which liquid water absorbs heat from a surface to evaporate into a gas, taking heat away and cooling the surface.

Cohesion

The property of water molecules sticking to one another due to hydrogen bonding.

Adhesion

The property of water molecules sticking to other polar surfaces or substances.

Xylem

The internal tubes in vascular plants that have polar walls, allowing water to adhere and travel upward from roots to leaves.

Capillary Action

The movement of water upward against gravity through narrow spaces, driven by a combination of cohesion and adhesion.

Surface Tension

An extension of cohesion where hydrogen bonds create a resistant film on the surface of water, allowing objects or organisms to rest on top without breaking through.

temperature

measure of kinetic nrg in mass/matter

idependent variable

A variable that is manipulated or changed in an experiment to observe its effect on the dependent variable. This variable is intentionally altered by the researcher to determine its impact on the outcome of the experiment.

dependent variable

The variable that is measured in an experiment and is affected by changes in the independent variable.