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Glossary of Chemical Oceanography Terms
Ionization: The process by which a neutral atom or molecule loses or gains electrons,
thereby acquiring a net charge and becoming an ion.
Phosphorescence: The emission of electromagnetic radiation from an excited molecule
from a triplet state to the ground state.
Photochemical Effect: A chemical reaction that takes place in the presence of light.
Photon: A massless particle, the quantum of the electromagnetic field, carrying energy,
momentum, and angular momentum (light quantum).
Photoreactions: Reactions that only take place in the presence of light.
Primary Photochemical Reaction: Reaction of a chromophore directly with light
(M + hv → M*).
Quantum Yield: The number of moles of a reactant disappearing or product produced
per photon of light absorbed for a photochemical reaction.
Redox Transients: States of an atom or molecule that are temporary and usually quickly
converted back to their original state, although conversion to a new state is possible.
Rotational States: The energy levels of an atom or molecule due to the spinning or rotation of the molecule around a preferred axis.
Secondary Photochemical Reaction: Reactions that result from the formation of a radical
(e – + O 2 → O 2
– ).
Singlet State: Spin paired state of an atom or molecule.
Spectra of Light: The wavelength or frequency of visible light.
Stark–Einstein Law: The second law of photochemistry, which states that an atom or
molecule undergoing a photochemical process absorbs only a single photon.
Superoxide Radical (O 2
– ): An intermediate in the formation of hydrogen peroxide. A
strong reducer that can result in the formation of reduced metals.
Triplet State: The state of an atom or molecule in which the spins of the electrons are
unpaired or are parallel.
Vibration States: The energy levels of an atom or molecule due to vibrations.
Wave Number: The reciprocal of the wavelength of light, or sometimes 2π divided by the
wavelength.
Hydrothermal Vent Chemistry
Black Smoker: Type of hot hydrothermal vent waters with an exit temperature of 350°C
and a flow rate of 1 to 2 m/ s.
Chemolithotrophy: Aerobic or anaerobic process whereby bacteria use reduced inorganic
compounds as a source of energy.
Chemosynthesis: Biosynthesis of organic compounds from carbon dioxide using energy
derived through chemical oxidation.
Hydrothermal Vents: Areas on the seafloor where active volcanism is found near areas
of continental rifts. The hot water coming out of these systems is formed by the
reactions of seawater with molten lava.
Photoautolithotropy: A type of photosynthesis used by green and purple bacteria and
green plants. The bacteria make usage of a nonoxygenic pathway while green
plants use oxygenic photoautolithotropy.
White Smoker: Type of hot hydrothermal vent waters with an exit temperature of 300°C
and a flow rate of 1 to 2 m/ s.
Glossary of Chemical Oceanography Terms
Ionization: The process by which a neutral atom or molecule loses or gains electrons,
thereby acquiring a net charge and becoming an ion.
Phosphorescence: The emission of electromagnetic radiation from an excited molecule
from a triplet state to the ground state.
Photochemical Effect: A chemical reaction that takes place in the presence of light.
Photon: A massless particle, the quantum of the electromagnetic field, carrying energy,
momentum, and angular momentum (light quantum).
Photoreactions: Reactions that only take place in the presence of light.
Primary Photochemical Reaction: Reaction of a chromophore directly with light
(M + hv → M*).
Quantum Yield: The number of moles of a reactant disappearing or product produced
per photon of light absorbed for a photochemical reaction.
Redox Transients: States of an atom or molecule that are temporary and usually quickly
converted back to their original state, although conversion to a new state is possible.
Rotational States: The energy levels of an atom or molecule due to the spinning or rotation of the molecule around a preferred axis.
Secondary Photochemical Reaction: Reactions that result from the formation of a radical
(e – + O 2 → O 2
– ).
Singlet State: Spin paired state of an atom or molecule.
Spectra of Light: The wavelength or frequency of visible light.
Stark–Einstein Law: The second law of photochemistry, which states that an atom or
molecule undergoing a photochemical process absorbs only a single photon.
Superoxide Radical (O 2
– ): An intermediate in the formation of hydrogen peroxide. A
strong reducer that can result in the formation of reduced metals.
Triplet State: The state of an atom or molecule in which the spins of the electrons are
unpaired or are parallel.
Vibration States: The energy levels of an atom or molecule due to vibrations.
Wave Number: The reciprocal of the wavelength of light, or sometimes 2π divided by the
wavelength.
Hydrothermal Vent Chemistry
Black Smoker: Type of hot hydrothermal vent waters with an exit temperature of 350°C
and a flow rate of 1 to 2 m/ s.
Chemolithotrophy: Aerobic or anaerobic process whereby bacteria use reduced inorganic
compounds as a source of energy.
Chemosynthesis: Biosynthesis of organic compounds from carbon dioxide using energy
derived through chemical oxidation.
Hydrothermal Vents: Areas on the seafloor where active volcanism is found near areas
of continental rifts. The hot water coming out of these systems is formed by the
reactions of seawater with molten lava.
Photoautolithotropy: A type of photosynthesis used by green and purple bacteria and
green plants. The bacteria make usage of a nonoxygenic pathway while green
plants use oxygenic photoautolithotropy.
White Smoker: Type of hot hydrothermal vent waters with an exit temperature of 300°C
and a flow rate of 1 to 2 m/ s.