Chemical Names and Formulas Overview •Metals and Non-Metals •Ions and Ionic Charges •Types of Compounds •Systematic Names -Writing Names and Formulas
Metals and Nonmetals Stairway Of Division on Periodic Table C, P, Se, I, Rn and to the right are non- metals B, Si, As, Ge, Sb, Te, Po, At are semi- metals All others are metals
Ions Cations Positively Charged Atoms i.e. Na+ Anions Negatively Charged Atoms i.e. Cl-
IONIC CHARGES Group I -> Group II -> Group III -> Group IV -> 1+ 2+ 3+ 4+
IONIC CHARGES Group V -> Group VI -> Group VII -> Group VIII -> 3- 2- 1- Noble Gases
TYPES OF COMPOUNDS Ionic Compounds negative ions. to one another. • composed of positive and negative ions. • usually formed from a metal and non-metal. • these elements are not attached to one another.
TYPES OF COMPOUNDS Ionic Compounds con’t • Examples NaCl CaBr2 KI
CHEMICAL FORMULAS Definition i. e. NaCl • shows the kind and numbers of atoms in the smallest representative unit of the substance. i. e. NaCl
IONIC COMPOUNDS A formula unit is the lowest whole number ratio of ions in an ionic compound. i.e. Na2Cl2 -> NaCl There is no such thing as a molecule of NaCl!!!!!!!!!
IONIC COMPOUNDS If charges cancel, just write the symbols Na+1 Cl-1 NaCl If charges do not cancel, criss-cross: Ca+2 Cl-1 CaCl2 ***Do not move the charge, only the number ***Do not write the 1
NAMING COMPOUNDS Your ability to name compounds and write formula’s hinges on your ability to recognize whether a compound is Ionic or Molecular.
BINARY IONIC COMPOUNDS Binary means 2 elements Ionic means a metal and a non-metal (or cation and anion) Writing Formulas • charges must balance so compound charge is neutral.
BINARY IONIC COMPOUNDS Writing Formulas from Names • 1st word = CATION • 2nd word = ANION name with ide ending.
BINARY IONIC COMPOUNDS NaBr MgF2 Sodium Bromide Magnesium Fluoride
BINARY IONIC COMPOUNDS Potassium Chloride Aluminum Oxide • notice ending of name is ide! K+Cl- -> KCl Al23+O32- -> Al2O3
Polyatomic Ions Definition •tightly bound groups of atoms that behave as a unit and carry a charge. Example SO32-, NO2-, ClO2-
TERNARY IONIC COMPOUNDS Ternary means 3 different elements Usually contain Poly-atomic Ions Ionic means cation and anion
TERNARY IONIC COMPOUNDS:Writing Formulas Ca2+CO32- CaCO3 Charges canceled. Just write the symbols Calcium Carbonate
TERNARY IONIC COMPOUNDS: Naming Calcium Nitrate Notice the charges didn’t cancel so they criss crossed Ca+2 (NO3)-1 Ca(NO3)2
Naming with Transition Metals First word = CATION Second word = ANION The Roman numeral will tell you the charge of the transition metal Silver (Ag) is an exception. It’s charge is +1
Naming Transition Metals Copper (I) Oxide Cu+1 O-2 Cu2O
Writing Formulas with Transition Metals FeCl3 Fe+3 Cl-1 FeCl2 Fe+2 Cl-1 Iron (III) Chloride Iron (II) Chloride *Backwards criss-cross to know the charge/Roman numeral
TYPES OF COMPOUNDS Molecular Compounds • composed of molecules in which elements share electrons. • usually composed of 2 nonmetals. • these elements are attached
MOLECULAR FORMULA Definition kinds of atoms present in a • shows the numbers and kinds of atoms present in a molecule of a compound. i. e. CO
TYPES OF COMPOUNDS Molecular Compounds con’t •Examples CS2 SiO2 BF3
BINARY MOLECULAR COMPOUNDS Binary means 2 elements Molecular means 2 non-metals NO ionic charges are present
Naming Binary Molecular Compounds Prefixes are used to show how many atoms are present in each molecule.
Covalent Prefixes Mono (or no prefix) – 1 Di – 2 Tri – 3 Tetra – 4 Penta – 5 Hexa – 6 Hepta – 7 Octa – 8 Nona – 9 Deca – 10
Writing Binary Molecular Compounds Carbon Dioxide • Di means 2 oxygens!! CO2 •no mono prefix is used on first element
Naming Binary Molecular Compounds 2 ways it’s done! • (prefix + element name) i.e. N2O dinitrogen monoxide
Naming Binary Molecular Compounds • (prefix + element root + ide) i.e. PCl3 Phosphorous Trichloride All binary compounds end in ide!!!