POLYATOMIC IONS (must be memorized POLYATOMIC IONS (must be memorized!) Polyatomic ions are mostly made of two non-metals. Ions with -1 charge chlorate ClO3- nitrate NO3- hydroxide OH- acetate C2H3O2- Permanganate MnO4- Cyanide CN- Ions with a -2 Charge carbonate CO3-2 sulfate SO4-2 Ions with a -3 Charge phosphate PO4-3 Ions with +1 charge ammonium ion NH4+

Polyatomic Ions Rules Changing the number of oxygens (in reference to the --ate) changes the name of the ion perchlorate ClO4-1 chlorate ClO3-1 chlorite ClO2-1 hypochlorite ClO-1 Add 1 O  add per- prefix --ate is the baseline Subtract 1 O  change to –ite Subtract 2 O  hypo--ite

More Rules to remember Adding a hydrogen to the ion changes the name and the charge carbonate CO3-2 bicarbonate HCO3-1 --ate is the baseline Add 1 H  add bi- prefix & +1 to charge

-1 These polyatomic ions match the charge of the single element Ions with -1 charge perchlorate ClO4-1 chlorate ClO3-1 chlorite ClO2-1 hypochlorite ClO-1