C3 Quantitative Chemistry

• Ionic compounds


  Formed when metals react with non-metals
• Charges on ions


  • Metals form positive ions
  • Non-metals form negative ions
• Charge on metal ion


  Equal to the group number (except group 1)
• Transition metals


  • Can form several ions
  • Common charges are 2+ and 3+
• Charge on non-metal ion

  Equal to the group number (group 7 = -1)
• Formula of ionic compounds

  1. Charges on ions must balance

  2. Simplest whole number ratio
• Ionic compounds


  • Sodium chloride (NaCl)
  • Sodium oxide (Na2O)
  • Magnesium iodide (MgI2)
  • Lithium carbonate (Li2CO3)
  • Calcium hydroxide (Ca(OH)2)
  • Magnesium nitrate (Mg(NO3)2)
• Chemical formula


  • Capital letters represent elements
  • Numbers represent the number of atoms of each element
• Sodium Carbonate


  • Na2 = 2 atoms of Sodium, C = 1 Carbon, 3 = 3 atoms of Oxygen
• You are never allowed to change the small numbers in a chemical formula
• Changing the small numbers produces a different molecule
• 3 Na2CO3


  • The large number 3 means we have 3 molecules of Sodium Carbonate
• Sodium Carbonate + Calcium Chloride

  1. Calcium + Chlorine

  2. Calcium Chloride
• The equation is balanced because both sides have the same number of each element
• Sodium + Iodine


  Sodium Iodide
• Calcium oxide + Hydrochloric acid


  Calcium Chloride + Water
• Iron oxide + Carbon monoxide

  Iron + Carbon dioxide