OCS1005 - Chemical Oceanography Exam Prep

wave length (L)

the horizontal distance between successive wave crest

wave height (H)

the vertical distance between wave crest and trough

wave period (T)

time required for a wave to move the distance of one wavelength (one crest to the next crest)

wave speed (or phase speed)

how fast the wave moves (C = L/T)

wave frequency

f = 1/T (reciprocal of T)

the ___ is the highest part of a wave

crest

the ___ is the lowest part of a wave

trough

Waves transmit ___, not water mass, across the ocean’s surface

energy

the most important waves are…

wind waves, tsunamis, and tides

orbital wave motion is ___ towards the surface of the ocean

larger

orbital wave motion becomes ___ as you go down

smaller

deep-water waves

little orbital motion that occurs at depths greater than half the wave length

waves that do not reach the bottom of the sea floor

deep-water

waves that reach the bottom of the sea floor

shallow-water

for a ___, the wave speed decreases as the water depth decreases

shallow-water wave

waves begin to break when…

wave steepness (H/L) exceeds 1/7 (or the wave crest forms an angle less than 120 degrees)

significant wave height

the average height of the highest one-third f the waves present

dispersive waves

waves where the wave speed depends on the wave period

non-dispersive waves

waves where the wave speed does NOT depend on the wave period

an example of dispersive waves

deep-water waves

an example of non-dispersive waves

shallow-water waves

waves with the longest wavelength move the…

fastest and leave the area of wave formation sooner

wind waves/ wind seas

locally generated waves

ocean swells

not locally generated waves

fetch

the uninterrupted distance over which the wind blows without significant change in direction

ocean waves are generated by…

wind blowing over the ocean surface

factors that affect wind wave development

wind strength, wind duration, fetch

wave refraction

the bending of waves in shallow water

wave diffraction

propagation of a wave around an obstacle

wave reflection

waves “bounce back” from an obstacle

waves always bend ___ slower propagation speed media

towards

in a more shallow area, wave speed is ___

faster

in a deeper area, wave speed is ___

slower

storm surge

the abnormal rise of water generated by a storm, over and above the predicted astronomical tide

in the ___ hemisphere, the right hand side of a hurricane is always larger than the left hand side

northern

in the ___ hemisphere, the left hand side of a hurricane is always larger than the right hand side

southern

storm tide

the total observed seawater level during a storm, which is the combination of storm surge and normal high tide

constructive interference

additive interference that results in waves larger than the original waves

destructive interference

two waves that cancel each other out, resulting in reduced or no wave

rouge waves

these freak waves occur due to the interference and result in wave crest higher than the theoretical maximum

tsunami are caused mainly by ___

earthquakes or landslides

what kind of waves are tsunami waves considered?

shallow-water wave

number of protons wants to equal the number of _____

electrons

proton equals

positive

neutron equals

neutral

electron equals

negative

protons and neutrons are bound together to form a _____

nucleus

opposite charges _____

attract

like charges _____

repel

valence shell

the outermost shell of an atom

all chemical reactions are related to the number of electrons in the _____

valence shell

inner most shell needs…

2

outer most shell needs…

8

atomic number

the number of protons in an atom

isotopes

atoms with the same atomic number (Z) but different neutron numbers (N) and hence different atomic masses

isotopes can be divided into _____ types

two

stable

persist in nature

radioactive

no stable and undergo nuclear change to reach stable

radioactive isotopes

emit particles or electromagnetic radiation from the nucleus to get to a stable species

half life

the time required for an unstable atom to reduce to half its initial value (radioactive decay)

three quarters of naturally occurring elements have ____

isotopes

_____ is the most abundant atom in the universe, making up about 90% of the universe by weight

hydrogen

cation

a positively charged ion

anion

a negatively charged ion

ions are mostly generated by _____ electron(s) at the valence shell

gaining or losing

molecule

an electrically neutral group of two or more atoms held together by chemical bonds

homonuclear molecule

composed of atoms of one chemical element

heteronuclear molecule (chemical compound)

composed of 2 or more different elements (Ex: water)

covalent bond

a chemical bond that involves the sharing of electron pairs between atoms

ionic bond

a chemical bond that involves the electrostatic attraction between oppositely charged ions

French chemist _____ discovered that water can be divided into two gases

Lavoisier

H2O is held together by _____ (electrons are shared)

covalent bonds

example of strong bond (primary bond)

covalent or ionic bonds

example of weak bond (secondary bond)

hydrogen bonding

water is special because of its ______

hydrogen bond

cohesion

water molecules stick together

adhesion

tendency of water to stick to other materials

capillary action

caused by cohesion and adhesion

blue color of pure water

water molecules vibrate, absorbing red light which leaves behind more blue light

the maximum water density is _____

4 degrees C

water is a _____ molecule

polar

water’s unusual properties are due to…

intermolecular hydrogen bonding

solution

made of two components with uniform properties throughout

solvent

(usually a liquid) is the more abundant component

solute

(usually a dissolved solid or gas) is the less abundant component

in a _____, the components are closely intermingled but remain separated

mixture

water is the known as the…

universal solvent

the solutes move through still water by _____

diffusion

saturated

no more will dissolve

precipitation

solute forming crystals from solution

solubility

the maximum amount of solute dissolved in a solvent at equilibrium

main element traces in oceans

most abundant ions, minor elements, trace elements

salinity

the total mass of dissolved inorganic solids in grams in 1 kg of seawater (ppt or g/kg)

average ocean water salinity

35ppt

forchhammer’s principle

states that although the salinity of various samples of seawater may vary, the ratio of major salts is constant

how to measure salinity

principle of constant proportions

salt exists in sea water in _____ states

ionic

salinity increases → _____ capacity decreases

heat

salinity increases → _____ point decreases

freezing

salinity increases → _____ slows

evaporation