Ionic Compounds Ionic Bonding Electrons are transferred from one atom to another so that each has 8 valence electrons - called the octet rule + Cation Anion Ionic Compound Ionic bond: bond formed by attraction between + and - ions Ionic Bonding Ionic bonds occur between metals and non-metals H He Li Be B C N O F Ne Na Mg Al Si P S Cl Ar K Ca Sc Ti V Cr Mn Fe Co Ni Cu Zn Ga Ge As Se Br Kr Rb Sr Y Zr Nb Mo Tc Ru Rh Pd Ag Cd In Sn Sb Te I Xe Cs Ba Lu Hf Ta W Re Os Ir Pt Au Hg Tl Pb Bi Po At Rn Fr Ra Lr Rf Db Sg Bh Hs Mt Uun Uuu Uub Uut Metals Metalloids Non-metals The “magic number” is 8! Binary Ionic Compounds Formula to Name The Language of Chemistry Chemistry has a language all of its own Chemistry English Element Symbols Letters Chemical Formulas Words Chemical Equations Sentences Each element symbol starts with a capital letter Binary Ionic: Formula to Name • These compounds have: – 2 elements (“binary”) – A metal & a non-metal (“ionic”) • To name: 1. Name of the metal (the cation) 2. Name of the non-metal (the anion) with the suffix “-ide” The subscripts in the formula do not matter when naming this type Example CaBr2 Example K2O Let’s Practice Example: Write the name for the following compounds CaF2 Na3P NaI SrBr2 Let’s Practice Example: Write the name for the following compounds CaF2 Calcium fluoride Na3P Sodium phosphide NaCl Sodium chloride SrBr2 Strontium bromide Binary Ionic Compounds Name to Formula Binary Ionic: Name to Formula • These compounds: – End in “-ide” (except “hydroxide and cyanide”) – Do NOT contain covalent prefixes • To write: 1. Draw Lewis dot diagrams of each element and transfer electrons. 2. Use subscripts to show how many of each type of ion you have. Example Sodium fluoride Let’s Practice Example: Write the following chemical formulas Cesium chloride Potassium oxide Calcium sulfide Lithium nitride Let’s Practice Example: Write the following chemical formulas Cesium chloride CsCl Potassium oxide K2O Calcium sulfide CaS Lithium nitride Li3N Multivalent Ionic Compounds Formula to Name Multivalent (Transition) Metals Multivalent Metal: a metal that has more than one possibility for cationic (positive) charge The Appendix of your book (Page A-2) has the following chart Common multivalent metals and their charges Cobalt Copper Iron Lead Manganese Mercury Tin Co+2 Cu+1 Fe+2 Pb+2 Mn+2 Hg2+2 Sn+2 Co+3 Cu+2 Fe+3 Pb+4 Mn+3 Hg+2 Sn+4 Multivalent Metals: Formula to Name • To identify: – Have a transition metal • To name: 1. 2. 3. 4. 5. 6. Name of the metal cation Name of the anion Determine total negative charge in the compound Total negative charge must = total positive charge Determine the charge on each metal atom Write the charge in roman numerals in parenthesis after the metal’s name Example Anion CuCl2 Total Total negative positive charge in charge in compound compound Cation Name Example Anion Fe2O3 Total Total negative positive charge in charge in compound compound Cation Name Let’s Practice PbCl2 Example: Write the name for the following compounds PbCl4 MnO Mn2O7 Let’s Practice Example: Write the name for the following compounds PbCl2 Lead (II) chloride PbCl4 Lead (IV) chloride MnO Manganese (II) oxide Mn2O3 Manganese (VII) oxide Multivalent Ionic Compounds Name to Formula Multivalent Metals: Name to Formula • To identify: – Will have roman numerals • To write: – Same as binary! • Roman numerals tell the charge of the metal cation Example Iron (III) oxide Example Copper (I) nitride Let’s Practice Example: Write the following chemical formulas Iron (II) nitride Copper (I) chloride Lead (IV) sulfide Tin (II) oxide Let’s Practice Example: Write the following chemical formulas Iron (II) nitride Fe3N2 Copper (I) chloride CuCl Lead (IV) sulfide PbS2 Tin (II) oxide SnO Polyatomic Ionic Compounds Polyatomic Ions Polyatomic Ion: a group of atoms that has lost or gained electrons. Therefore, it has a charge! Polyatomic Ionic Compound: compound containing at least one polyatomic ion + Cation Polyatomic Anion Polyatomic Ionic Compound Identifying Polyatomic Ions • Only one cation: NH4+ • All others are anions (second part of formula) • Subscripts must match exactly as it appears on your list • If there are parenthesis, the polyatomic ion is inside Practice Identifying Polyatomic Ions Example: Identify and name the polyatomic ion in each compound NaNO3 NH4Cl Ca(OH)2 (NH4)3PO4 K2CO3 Practice Identifying Polyatomic Ions Example: Identify and name the polyatomic ion in each compound NaNO3 Nitrate NH4Cl Ammonium Ca(OH)2 Hydroxide (NH4)3PO4 Ammonium & phosphate K2CO3 Carbonate Polyatomic Ionic Compounds Name to Formula Polyatomic Ionic: Name to Formula • • To identify: – Do not end with “-ide” (except hydroxide & cyanide) – Do not use covalent prefixes To write these formulas: 1. Write the symbol & charge of the cation & anion 2. Add additional cations or anions to have a neutral compound 3. Use subscripts to show the number of ions - When using subscripts with a polyatomic ion, you must put the polyatomic ion in parenthesis. Example Sodium carbonate Example Magnesium nitrate Let’s Practice Example: Write the following chemical formulas Sodium nitrate Calcium chlorate Potassium sulfite Calcium hydroxide Let’s Practice Example: Write the following chemical formulas Sodium nitrate NaNO3 Calcium chlorate Ca(ClO3)2 Potassium sulfite K2SO3 Calcium hydroxide Ca(OH)2 Polyatomic Ionic Compounds Formula to Name Polyatomic Ionic: Formula to Name • To identify: – More than 2 capital letters (not starting with H) – at least 1 metal & 1 non-metal • To name: 1. Name of the cation 2. If the anion is a polyatomic ion, write the polyatomic ion’s name just as it is 3. If the anion is a single non-metal element, use “-ide” Example NaNO3 Example Fe(OH) 2 Let’s Practice Ca(NO3)2 Example: Write the name for the following compounds Na3PO4 NH4ClO K2CO3