Help with redox equations!!Watch
Anions are negative as they gain electrons (Non metals)
Cations are positive as they lose electrons (if struggle to remember this remember that cats are PAWsitive) They are metal.
Remember this, "OIL RIG" (Oxidation is loss) (Reduction is gain) - of electrons. when something is reduced so is its oxidation number. the rules for oxidation are as followsfor AS LEVEL)
uncombined element ALWAYS = 0
simple/monatomic ion = charge of ion
combined oxygen = -2
combined hydrogen = + 1
combined fluorine = -1
Sum of all numbers in a compound must always = 0
silver = +1
(combined means with something else, not just on its own in element form)
Oxygen bonded to fluorine = +2.
When asked in exam question you must quote the numerical changes for whatever is oxidised and reduced and obviously state what is oxidised and reduced.