Nomenclature: Naming Compounds

Ionic Compounds  Formed when electrons are transferred from the less electronegative atom (Na) to the more electronegative atom (Cl). Na    e -1    Cl to give Na +1 and Cl  1 thus NaCl

Electronegativity  Tendency for atoms to attract electrons  Metals have low electronegativity  Metals lose electrons to form ions (Na +1 )  Non-metals have high electronegativity  Non-metals gain electrons to form ions (Cl  1 )

Ionic Compounds (NaCl)  Formed between metals and non-metals  Use element name of the metal (sodium)  Add –ide to root name of non-metal (chloride)  We have: sodium chloride

Predicting Charges on Monatomic Ions KNOW THESE !!!! Cd +2

The –ides Of Compound Names  Fluorine   Chlorine   Bromine   Iodine   Oxygen   Sulfur   Carbon   Nitrogen   Phosphorus  Fluoride Chloride Bromide Iodide Oxide Sulfide Carbide Nitride Phosphide

Name – ide Compounds  KCl   Na 2 O   CaS   MgBr 2   ZnCl 2   Ag 2 S   Al 2 O 3   CaC 2   K 3 N  Potassium chloride Sodium oxide Calcium sulfide Magnesium bromide Zinc chloride Silver sulfide Aluminum oxide Calcium carbide Potassium nitride

Polyatomic ions Special naturally ocurring ions that have their own names- they end in -ite, -ate or other

Names of Polyatomic Ions with Oxygen  Polyatomic ions usually contain oxygen in addition to another element.  Normally they have a negative charge.  They end in either "ate" or "ite" depending on the number of oxygen atoms present. ClO - hypochlorite ClO 2 - chlorite ClO 3 - chlorate ClO 4 - perchlorate NO 2 - Nitrite Nitrite NO 3 - Nitrate Nitrate PO 3 3- phosphite phosphite PO 4 3- phosphate phosphate SO 3 2- SO 4 2- sulfite sulfite sulfate sulfate

Name –ate Compounds  KNO 3   CaCO 3   AlPO 4   MgSO 4   Ca(NO 3 ) 2   K 3 PO 4   Al 2 (SO 4 ) 3   Mg 3 (PO 4 ) 2  Potassium nitrate Calcium carbonate Aluminum phosphate Magnesium sulfate Calcium nitrate Potassium phosphate Aluminum sulfate Magnesium phosphate

Some Other Polyatomics  OH  1   NH 4 +1   CN  1   HCO 3  1   HSO 4  1  Hydroxide Ammonium Cyanide Bicarbonate Bisulfate

Name Some Other Polyatomics  KOH   Al(OH) 3   NH 4 Cl   (NH 4 ) 2 SO 4   KCN   HCN   NaHCO 3   KHSO 4  Potassium hydroxide Aluminum hydroxide Ammonium chloride Ammonium sulfate Potassium cyanide Hydrogen cyanide Sodium bicarbonate Potassium bisulfate

Elements with Multiple Cations When an element can form more than one cation a Roman numeral is used to distinguish the oxidation state of the compound. Iron, Tin, Lead, Copper, and are common elements with more than one cation. Examples 1. PbSO 4 = lead (II) sulfate This compound is formed from Pb 2+ and SO Pb(SO 4 ) 2 = lead (IV) sulfate This compound is formed from Pb 4+ and SO Fe(OH) 2 = iron (II) hydroxide This compound is formed from Fe 2+ and OH - 4. Fe(OH) 3 = iron (III) hydroxide This compound is formed from Fe 3+ and OH -

Naming Covalent Compounds Chemistry Dr. May

Covalent Compounds  Formed when electrons are shared between two atoms having similar electronegativities  Formed between two non-metals such as sulfur (S) and oxygen (O) or carbon (C) and oxygen. SO SO 2 SO 3 SO 4 CO CO 2

Naming Guidelines – PBr 5  Less electronegative element comes first  Name of element (phosphorus)  Prefix needed if more than one atom  More electronegative element comes next  Prefix needed, even if 1 (mono)  Root name plus –ide (pentabromide)  PBr 5 is phosphorus pentabromide

Possible Prefixes  Oneis  Twois  Threeis  Fouris  Fiveis  Sixis  Sevenis  Eightis  Nineis  Tenis Mono- Di- Tri- Tetra- Penta- Hexa- Hepta- Octa- Nona- Deca-

Name Covalent Compounds  CO  CO 2  SO 2  SO 4  SF 6  NI 3  P 2 O 5  CCl 4 Carbon monoxide Carbon dioxide Sulfur dioxide Sulfur tetraoxide Sulfur hexafluoride Nitrogen triiodide Diphosphorus pentoxide Carbon tetrachloride