Section 2-2, Part 1: Writing chemical names

Section 2.2—Naming Chemicals :Section 2.2—Naming Chemicals We need to be able to name the chemicals in the antacids!


The Language of Chemistry :The Language of Chemistry Chemistry has a language all of its own Each element symbol starts with a capital letter English Chemistry Element Symbols Letters Chemical Formulas Words Chemical Equations Sentences


Binary Ionic compounds :Binary Ionic compounds


Definitions :Definitions Binary Ionic Compound- compound containing two elements—one metal and one non-metal + Cation - Anion Ionic bond- bond formed by attraction between + and - ions


Metals & Non-Metals :Metals & Non-Metals Ionic Bonds are between metals & non-metals


Identifying & Naming Binary Ionic :These compounds have: 2 elements (“binary”) A metal & a non-metal (“ionic”) To name these compounds: Write the name of the metal (the cation) Write the name of the non-metal (the anion) with the suffix “-ide” Identifying & Naming Binary Ionic The subscripts in the formula do not matter when naming this type


Example #1 :Example #1 NaCl


Example #1 :Example #1 NaCl Cation Anion “Sodium” “Chlorine” becomes “Chloride” Sodium Chloride


Example #2 :Example #2 CaBr2


Example #2 :Example #2 Cation Anion “Calcium” “Bromine” becomes “Bromide” CaBr2 Calcium Bromide


Example #3 :Example #3 K2O


Example #3 :Example #3 K2O Cation Anion “Potassium” “Oxygen” becomes “Oxide” Potassium Oxide


Let’s Practice :Let’s Practice Example: Write the name for the following compounds CaF2 Na3P NaCl SrBr2


Let’s Practice :Let’s Practice Calcium fluoride Sodium phosphide Sodium chloride Strontium bromide Example: Write the name for the following compounds CaF2 Na3P NaCl SrBr2


Polyatomic Ionic Compounds :Polyatomic Ionic Compounds


Definition :Definition Polyatomic Ion- more than one atom that together have a charge + Cation Polyatomic Ionic Compound- compound containing at least one polyatomic ion


Common Polyatomic Ions :Common Polyatomic Ions The Appendix of your book (Page A-2) has the following chart


Help Identifying Polyatomic Ions :The only cation (front-half) polyatomic ion is “NH4” All other polyatomic ions are anions (back-half) The subscripts within the polyatomic ion is important (it must match exactly with the one on your ion list) If there are parenthesis, the polyatomic ion is inside (ignore the number outside) Help Identifying Polyatomic Ions


Practice Identifying Polyatomic Ions :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 :Practice Identifying Polyatomic Ions Example: Identify and name the polyatomic ion in each compound NaNO3 NH4Cl Ca(OH)2 (NH4)3PO4 K2CO3 Nitrate Ammonium Hydroxide Ammonium & phosphate Carbonate


Identifying & Naming Polyatomic Ionic :These compounds have: More than 2 capital letters (non starting with H) Contain at least 1 metal & 1 non-metal To name these compounds: Write the name of the cation (the metal element name or “Ammonium” for “NH4”) If the anion is a polyatomic ion, write the polyatomic ion’s name just as it is If the anion is a single non-metal element, write its name with the suffix “-ide” Identifying & Naming Polyatomic Ionic


Example #4 :Example #4 NaNO3


Example #4 :Example #4 NaNO3 Cation Polyatomic Anion “Sodium” “Nitrate” Sodium Nitrate


Example #5 :Example #5 K2SO4


Example #5 :Example #5 Cation Polyatomic Anion “Potassium” “sulfate” K2SO4 Potassium sulfate


Example #6 :Example #6 Ca(OH)2


Example #6 :Example #6 Ca(OH)2 Cation Polyatomic Anion “Calcium” “hydroxide” Calcium hydroxide


Example #7 :Example #7 (NH4)2S


Example #7 :Example #7 Polyatomic Cation Anion “Ammonium” “sulfur” becomes “sulfide” (NH4)2S Ammonium sulfide


Let’s Practice :Let’s Practice Example: Write the name for the following compounds Ca(NO3)2 Na3PO4 NH4ClO K2CO3


Let’s Practice :Let’s Practice Calcium nitrate Sodium phosphate Ammonium hypochlorite Potassium carbonate Example: Write the name for the following compounds Ca(NO3)2 Na3PO4 NH4ClO K2CO3