DEFINITIONS Flashcards
acid -bronsted lowry
proton H+ donor
acid -arrhenius
produces H+( hydrogen ion) by dissociated in water (aqueous solution)
acidic oxide
oxide that lowers pH in water
activation energy
minimum energy needed for colliding particles to react
addition polymerisation
monomers combining to form a large molecule
absorption
the method of attachment of gaseous or liquid molecules to solid surface
AAS- atomic absorption spectrometry
instrumental method used to analyse water for heavy metals
atomic number
number of protons in nucleus
BOD - biochemical oxygen demand
amount of oxygen consumed in p.p.m. (mg1-1) when sample kept in dark for 5 days at 20C
atomic orbital
region around nucleus in which there is high probability of finding electron
atomic radius
half the distance between the centres of singly bonded atoms of the same element
atomic sub level
a sub division of a main energy level consisting of one or more orbitals of the same energy
auto ignition
tendency to premature ignition
avogadros law
equal volumes of gases contain equal numbers of molecules under same conditions of temperature and pressure
base-arrhenius
produces OH- as only an ion in aqueous solution
base -bronsted lowry
proton H+ acceptor
bond energy
average energy required to break 1 mole of bonds into separate atoms in the gaseous state
boyles law
PV=k at constant temperature
catalyst
substance that alters rate of reaction and is not used up
catalytic cracking
splitting of long chain molecules by heat and catalyst
catalytic poison
substance that blocks the active site of a catalyst and stops it working
charles law
V/T=k at constant pressure
chemical equilibrium
state in which rate of forward reaction = rate of reverse reaction
chromatography
separation of a mixture of components based on their relative attractions for a stationary phase while carried in a mobile phase
Condensation reaction
Production of a more complex molecule with formation of an unsaturated compound (or double bond) by the loss of a small molecule
Conjugate acid (bronsted Lowry)
Produced by gain of one proton (H+)
Conjugate pair
Acid base differing by proton
Covalent bond
Involving the sharing of one or more pairs of electrons
Crystals
Regular solids made up of particles (atoms,ions,molecules) with fades intersecting at iced (definite, specific, characteristic) angles or consisting of particles in a lattice
Dobereiners triads
Elements of similar properties in groups of three
Dynamic
Reaction has not stopped
Effective collision
One that results in a reaction
Electrolysis
Chemical reaction caused by electric current passing through an electrolyte
Electronegativity
Measure of relative attraction for shared electrons
Element
An element cannot be broken down into anything simpler
Energy level
Shell which electrons of equal energy can occupy
Equilibrium
Rate of forward reaction = rate of reverse reaction
Eutrophication
Excess plant growth caused by excess nutrient in water