Polyatomic Ions, Monatomic Ions and Elements (Honors Chemistry; Nomenclature/Bonding Unit)
Polyatomic ions are groups of multiple atoms that have a charge (positive or negative). The symbols shown below
tell you what elements are in the ion, how many atoms of each, and the charge. For example,
contains a
nitrogen atom, three oxygen atoms, and the entire group has a charge of -1.
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Memorization Hints: Polyatomic Ions
If you have two ions with similar names and the only difference is the number of oxygen atoms in your ion:
-ite means smaller number of O
-ate means larger number of O
Hypo- (smallest) and Per- (largest) are used if there are four ions with similar names and different numbers of oxygen.
Positive Polyatomic Ions (Polyatomic Cations)
1+
Ammonium (NH4 +)
Hydronium (H3O+)
Negative Polyatomic Ions (Polyatomic Anions)
1Acetate (C2H3O2-)
Chlorate (ClO3-)
Chlorite (ClO2-)
Cyanide (CN-)
Dihydrogen phosphate (H2PO4-)
Hydrogen Carbonate or bicarbonate (HCO3-)
Hydrogen Sulfite or bisulfite (HSO3-)
Hydroxide (OH-)
Hypochlorite (ClO-)
Nitrate (NO3-)
Nitrite (NO2-)
Perchlorate (ClO4-)
Permanganate (MnO4-)
Thiocyanate (SCN-)
2Carbonate (CO32-)
Chromate (CrO42-)
Dichromate (Cr2O7 2- )
Hydrogen Phosphate (HPO4 2- )
Oxalate (C2O42-)
Peroxide (O2 2- )
Sulfate (SO4 2- )
Sulfite (SO3 2- )
3Arsenate (AsO4 3- )
Phosphate (PO4 3- )
Remember that there are many online
resources available on the classroom
website. Use your flashcards from the
summer assignment to help you memorize
the required ions and elements.
Monatomic Ions:
Elements and Symbols List:
Hydrogen
H
Gallium
Ga
Helium
He
Germanium
Ge
Lithium
Li
Arsenic
As
Beryllium
Be
Selenium
Se
Boron
B
Bromine
Br
Carbon
C
Krypton
Kr
Nitrogen
N
Rubidium
Rb
Oxygen
O
Strontium
Sr
Fluorine
F
Yttrium
Y
Neon
Ne
Zirconium
Zr
Sodium
Na
Palladium
Pd
Magnesium
Mg
Silver
Ag
Aluminum
Al
Cadmium
Cd
Silicon
Si
Tin
Sn
Phosphorous
P
Antimony
Sb
Sulfur
S
Tellurium
Te
Chlorine
Cl
Iodine
I
Argon
Ar
Xenon
Xe
Potassium
K
Cesium
Cs
Calcium
Ca
Barium
Ba
Scandium
Sc
Tungsten
W
Titanium
Ti
Platinum
Pt
Vanadium
V
Gold
Au
Chromium
Cr
Mercury
Hg
Manganese
Mn
Thallium
Tl
Iron
Fe
Lead
Pb
Cobalt
Co
Bismuth
Bi
Nickel
Ni
Radon
Rn
Copper
Cu
Radium
Ra
Zinc
Zn
Uranium
U