you must know that charge of
H+ ion is [1+]
while O2- ions is [2-]
therefore charge of NH4+
N+ [+1]x4= 1
N=-3
chrage of NH4+ is -3
in No3-,
N+[-2]x3=-1
N=5
charge of No3=+5
2007-08-07 17:05:53 補充:
type wrong...should be "oxidation number"(氧化數) instead or "charge"oxidation number of NH4 is -3oxidation number of NO3- is 5