chem prefix notes part 2 for ionic compounds
Name | Formula | Charge | Notes (Prefix/Suffix) |
|---|---|---|---|
Hypochlorite / Hypobromite / Hypoiodite | ClO⁻ / BrO⁻ / IO⁻ | –1 | “hypo–” = least O, “–ite” ending |
Chlorite / Bromite / Iodite | ClO₂⁻ / BrO₂⁻ / IO₂⁻ | –1 | “–ite” = less O |
Chlorate / Bromate / Iodate | ClO₃⁻ / BrO₃⁻ / IO₃⁻ | –1 | “–ate” = more O |
Perchlorate / Perbromate / Periodate | ClO₄⁻ / BrO₄⁻ / IO₄⁻ | –1 | “per–” = most O, “–ate” |
Tip: Charge always –1; oxygen count increases from hypo → –ite → –ate → per–ate.
2⃣ Common Polyatomic Ions
Name | Formula | Charge | Notes |
|---|---|---|---|
Ammonium | NH₄⁺ | +1 | Only common positive polyatomic ion |
Hydroxide | OH⁻ | –1 | |
Nitrate | NO₃⁻ | –1 | –ate suffix, more O than nitrite |
Nitrite | NO₂⁻ | –1 | –ite suffix, fewer O than nitrate |
Sulfate | SO₄²⁻ | –2 | –ate suffix, more O than sulfite |
Sulfite | SO₃²⁻ | –2 | –ite suffix, fewer O than sulfate |
Phosphate | PO₄³⁻ | –3 | –ate suffix, most common form |
Carbonate | CO₃²⁻ | –2 | –ate suffix |
Hydrogen carbonate / Bicarbonate | HCO₃⁻ | –1 | |
Peroxide | O₂²⁻ | –2 | Two oxygens bonded together |
Chromate | CrO₄²⁻ | –2 | –ate suffix |
Dichromate | Cr₂O₇²⁻ | –2 | Two chromate units |
Acetate | C₂H₃O₂⁻ | –1 | Often written as CH₃COO⁻ |