definitions :) Flashcards
isotopes
two ATOMS of the SAME ELEMENT that have DIFFERENT relative atomic masses, so each atoms has a DIFFERENT NO. of NEUTRONS
relative isotopic mass
the MASS of an ATOM of an ISOTOPE compared to 1/12 of the mass of an atom of carbon-12 which has a mass of 12
relative atomic mass (Ar)
the WEIGHTED AVG. MASS of an ATOM of an ELEMENT compared to 1/12 of the mass of an atom of carbon-12 which has a mass of 12
ionisation energy (1st IE)
the ENERGY requires to remove ONE MOLE of ELECTRONS from ONE MOLE of atoms of the element in the GASEOUS state (to from ONE MOLE of +1 ions) (endothermic reaction)
electronegativity
the ABILITY of an ATOM to ATTRACT an ELECTRON PAIR in a covalent bond
mole
amount of substance that contains the same no. of particles as the no. of carbon atoms in 12g of carbon-12 ..
theoretical yield
the max. possible mass of a product, so no losses in mass
actual yield
the actual yield obtained in the reaction by weighing not by calculation
Avogadro’s constant
6.02 times 10^23
the no. of particles in a mole
relative molecular mass (Mr)
the AVG. MASS of a MOLECULE of a COMPOUND compared with 1/12 of the mass of an atom of carbon-12
molar mass (also Mr)
the mass per mole of substance in g/mol
homologous series
SAME FUNCTIONAL GROUP hence SAME CHEMICAL PROPERTIES and SAME GENERAL FORMULA (e.g. alkanes)
isomers
molecules/compounds with SAME MOLECULAR FORMULA and DIFFERENT STRUCTURAL FORMULA
structural isomers
same molecular formula but different structural formula
stereoisomers
same molecular formula and same structural formula but different arrangements of atoms
saturated hydrocarbon
hydrogen and carbon compounds with single c-c bonds so no more bonds can form (e.g. alkenes)
unsaturated hydrocarbon
hydrogen and carbon compounds with double (or triple) c=c bonds (e.g. alkanes)
cracking
process to BREAK down LONGER CHAIN FRACTIONS, which are often overproduced, to MORE USEFUL, SHORTER CHAIN FRACTIONS (that aren’t naturally present in crude oil)
reforming
process to obtain more useful fractions from less useful ones, under heat and pressure branched chain hydrocarbons are formed into longer, straight chained hydrocarbons
homolytic fission
breaking of covalent bonds so that one electron goes to each atom
heterolytic fission
breaking of covalent bonds so that both electrons goes to the same atom
functional group isomers
isomers that contain DIFFERENT functional groups hence they belong to DIFFERENT homologous series
