Anion
A negatively charged ion
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Anode
The electrode at which oxidation occurs in a cell. Anions migrate
to the anode.
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Boiling Point
The temperature at which the vapor pressure of a liquid is equal
to the external pressure on the liquid.
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Cathode
The electrode at which reduction occurs. Cations migrate to the
cathode
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Cation
A positively charged ion
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Chemical Potential
Free energy change per mole of a specific reactant
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Colligative Properties
Properties of a solution which depend on the number of solute molecules
present but not on the nature of the solvent. Examples are osmotic
pressure, vapor pressure,freezing point depression and boiling point
elevation.
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Corrosion
Oxidation of a metal.
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Dialysis
The selective passage of ions and small molecules, over proteins.
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Electrochemical
Potential
Free energy change per mole
of electrons transferred.
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Electrolysis
The passgae of a strong electric current through a molten ionic
compound resulting in decomposition of compound into its elements,
eg NaCl into Sodium metal and Chlorine gas
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Electrostatic
Interactions arising due to partial or whole charges on neighbouring
atoms or molecules
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Equilibrium
Dynamic equilibrium is established when two opposing forces
are occuring at the same rate, so there is no apparent change in
the system over long periods of time.
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Free
Energy
Energy that is available to do useful work. A decrease in free
energy accompanies any spontaneous process.
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Freezing Point
When the processes of freezing and thawing are in equilibrium
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Galvanise
Zinc plating a metal which has a less negative reduction
potential will protect the metal as the zinc is oxidised in preference.
This is called galvanising
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Hydrogen Bonds
Weak ionic attraction formed when a hydrogen atom carrying
a partial positive charge is near a small O, N or F atom which is
carrying an excess negative charge
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Molality
Concentration measured as moles of solute per kilogram of solvent.
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Molarity
Concentration measures as moles of solute per litre of solution
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Mole
An amount equal to the number of carbon atoms in exactly 12 grams
of the C12
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Mole fraction
Concentration of a substance in a mixture measured as moles of
the substance per mole of complete mixture.
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Osmosis
Passage of solvent molecules from a dilute solution through a semipermeable
membrane to a more concentrated solution
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Osmotic Pressure
Pressure which must be applied to a solution to prevent water from
flowing in via a semi-permeable membrane
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Oxidation
The loss (or partial loss) of one or more electrons by an atom,
molecule or ion.
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Partial Pressure
The partial pressure of a gas is the pressure that it would exert
if it occupied the container alone.
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Polar and Nonpolar
Polar molecules have an uneven charge distribution over their surface
as the bonding electron pair sit closer to one atom than the other,
one example is Water. Nonpolar molecules have an even charge distribution
such as methane.
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Porous
Having microscopic holes that allow the passage of small particles.
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Reduction
The gain (or partial gain) of one or more electrons by an atom,
molecule or ion.
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Reduction
Potentials
The reduction potential for any substance is the cell reaction
for theat substance in combiination with the Standard Hydrogen Electode.
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Semipermeable membrane
A membrane that allows some but not all of the components in a
mixture to pass through it. Semipermeable membranes are used in
dialysis.
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Spontaneous
Spontaneous processes do not require work to be done in order to
occur.
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Van der Waals attractions
These are interactions between molecules which leave their chemical
identis unchanged such as the interactions between the partial charges
on polar molecules.
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Vapor Pressure
The vapor pressure of a liquid is the pressure above the liquid
when the liquid and vapor phases are in dynamic equilibrium.
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