Marine U1: Water terms

Kinetic Particle Theory

how atoms and molecules move in relation to each other and the amount of energy within the system

Water Vapour

gaseous state of water

Protons

the subatomic particles of the nucleus that have a positive charge

neutrons

the subatomic particles of the nucleus that have no charge

electrons

The subatomic particles that orbit the nucleus with negative charge

Nucleus

the positively charged central core of an atom that contains protons and neutrons

shells

each of a set of orbitals around the nucleus of an atom that can be occupied by electrons

atomic number

the number of protons in the nucleus of an atom

Bond

a strong force of attraction holding atoms together in a substance

element

A substance that cannot be chemically broken down into simpler substances

compound

substance containing two or more elements chemically bonded together

molecule

atoms that are covalently bonded together

atom

smallest particle an element can be divided into and still be the same substance

emergent properties

Characteristics of a compound that are different from those of the elements that make it up

covalent bond

bond that involves sharing electron pairs between atoms

ionic bond

formed from the attraction between two oppositely charged ions

hydrogen bond

weak bond between two molecules due to the electrostatic attraction between a hydrogen atom in one molecule and an atom of O, N, or F in another molecule

ion

An atom or group of atoms that has gained or lost electrons creating a positive or negative charge.

polar

Opposite sides of a molecule have contrasting partial charges

solvent

a substance that can dissolve other substances

density

a measure of the mass of a defined volume of water

specific heat capacity

the energy required to raise the temperature of one gram of a substance one degree C

solute

the solid that dissolves

solution

a mixture of a solute dissolved in a solvent

dissolution

the process of being dissolved

salinity

A measured quantity of dissolved solids in ocean water. Represented by parts per thousand (ppt)

precipitation

water that falls from the atmosphere to the Earth's surface

run-off

the flow of water from land caused by precipitation

evaporation

The change of state from a liquid to a gas below the boiling point of a substance

hypersaline

when a body of water has a salinity greater than 40 ppt

halocline

a layer of water below the mixed surface layer where a rapid change in salinity can be measured as depth increases

thermocline

a layer between two layers of water with different temperatures

pH

numerical value expressing the number of hydrogen ions in the solution on a logarithmic scale

acidic

a pH below 7

alkaline

a pH above 7

neutral

pH of 7

pH scale

measures the ratio of hydrogen ions to hydroxide ions (logarithmic)

turbulence

irregular changes in the speed and direction of fluid movement

Dissolved oxygen

The concentration of oxygen dissolved in a solution

phytoplankton

photosynthetic organisms found in the upper water layers

oxygen minimum layer

the layer within the ocean where the concentration of DO is at its lowest typically below the photic zone

water column

a vertical section of water from the surface to the bottom; useful concept when discussing changes in the abiotic factors within the body of water

gradient

the rate of change in the y-axis value as the x-axis value increases

thermal insulator

a substance that reduces the transfer of heat energy

pycnocline

A layer of water between two layers of water with different densities

principle of constant proportions

the ratios between the major constituent ions in seawater is constant

solubility

the ability to dissolve