Common Polyatomic Ions

Flashcards to help with memorizing Common Polyatomic Ions for Ms. Holt's Chemistry class. If you’re the type of person, listen to this song for hours on loop to help remember ions: https://youtu.be/4nrrMcozp_Q

ammonium

ammonium

NH₄+

nitrite

NO₂-

nitrate

NO₃-

hydrogen sulfate

HSO₄-

hydroxide

OH-

cyanide

CN-

permanganate

MnO₄-

hydrogen carbonate

HCO₃-

hypochlorite

ClO-

chlorite

ClO₂-

chlorate

ClO₃-

perchlorate

ClO₄-

bromate

BrO₃-

iodate

IO₃-

Which ion is the only one with a positive charge in this study set?

Ammonium

periodate

IO₄-

acetate

C₂H₃O₂-
(“ate” pattern does not apply)

dihydrogen phosphate

H₂PO₄-

carbonate

CO₃²-

sulfite

SO₃²-
(“ite” pattern does not apply)

sulfate

SO₄²-

thiosulfate

S₂O₃²-

peroxide

O₂²-

chromate

CrO₄²-

dichromate

Cr₂O₇²-

hydrogen phosphate

HPO₄²-

phosphate

PO₄³-

arsenate

AsO₄³-

Ions with 3, 4, or more oxygen atoms will have a suffix (end part) of…

“ate,” except acetate
(this pattern only really applies in this study set)

Ions with less than 2 oxygen atoms will typically have a suffix (end part) of…

“ite”
(this pattern only really applies in this study set)

If there is “Hydrogen” in the name, how many hydrogen atoms will be in the ion?

1 hydrogen atom
(Ex. hydrogen sulfate, hydrogen carbonate)

If there is “dihydrogen” in the name, how many hydrogen atoms will be in the ion?

2 hydrogen atoms
(Ex. dihydrogen phosphate)

If there is “ni” in the name, what will be in the compound?

nitrogen
(Ex. nitrite, nitrate, cyanide)