Water Chemistry and Physical Properties Flashcards

Vocabulary practice flashcards covering water polarity, hydrogen bonding, heat capacity, cohesion, adhesion, density anomalies, and gas solubility dynamics.

Polar Covalent Bond

A chemical bond within a water molecule where electrons are shared unevenly because oxygen, the second most electronegative element, attracts electrons more strongly than hydrogen.

Hydrogen Bond

An intermolecular attraction between the partial negative charge of an oxygen atom in one water molecule and the partial positive charge of a hydrogen atom in a neighboring water molecule.

Temperature

A measure of the amount of kinetic energy present in the atoms or molecules of a substance.

Heat Capacity

The amount of heat energy required to change the temperature or physical state of a substance, which is exceptionally high in water due to hydrogen bonding.

Cohesion

The ability of water molecules to attach and hold onto other water molecules through hydrogen bonding.

Surface Tension

The elastic film created at the air-water interface because cohesive forces pull surface water molecules downward and sideways without an upward pulling force.

Adhesion

The property that allows polar water molecules to stick to other polar substances or surfaces.

Universal Solvent

A term for water describing its ability to dissolve ionic compounds, polar molecules, nutrients, and gases by surrounding charged ions with partial molecular charges.

Water Parcel

A discrete mass of water with distinct temperature, density, and solute concentrations that can move through aquatic environments.

Maximum Density Temperature of Freshwater

The temperature of $4^\bullet\text{C}$, at which pure freshwater reaches its highest density before expanding into a less dense open crystalline lattice as it cools toward freezing.

Henry's Law

A physical chemical law stating that as the partial pressure of a gas above a liquid increases, the concentration of that gas dissolved in the liquid increases proportionally.

Bicarbonate Equilibrium

The chemical reaction pathway that allows carbon dioxide ($\text{CO}_2$) to dissolve in water at significantly higher concentrations than predicted strictly by Henry's law.

Limnic Eruption

A rare natural disaster in which deep lake turnover rapidly releases large amounts of dissolved carbon dioxide ($\text{CO}_2$) gas into the atmosphere, suffocating living organisms in surrounding low-elevation areas.