Definitions Flashcards
Isotope
Atoms of the same element with different numbers of neutrons and therefore different masses
Relative isotopic mass
the mass of an atom of an isotope compared with 1/12th of the mass of an atom of carbon-12
Relative atomic mass
the wieghted mean mass of an atom of an element compared with 1/12th of the mass of an atom of carbon-12
Relative molecular mass
the weighted mean mass of a molecule compared with 1/12th of the mass of carbon-12
Relative formula mass
the weighted mean mass of a formula unit compared with 1/12th of the mass of carbon-12
1st ionisation energy
The amount of energy required to remove one electron from each atom in one mole of gaseous atoms to form one mole of gaseous 1+ ions
- Nuclear charge
- shielding
- atomic radius
- nuclear attraction
Oxidation
the loss of electrons ((formation of +ions))
an increase in the oxidation number (becomes more positive)
Reduction
the gain of electrons ((formations of -ions))
a decrease in oxidation number (becomes less positive)
Oxidising agent
a reagent that oxidises (takes electrons from) another species
Reducing agent
a reagent that reduces (gives electrons to) another speicies
Acid
an acid releases H+ ions in aqueous solution
an acid is a proton donor
weak acid / strong acid
A strong acid is fully dissociated in solution and a weak acid partially partially dissociated
Base
A proton acceptor
Alkali
A soluble base that releases OH- ions in water (/solution)
Salts
Salts are ionic compounds formed when the H+ ions in an acid are replaced by metal or ammonium ions