Formulas

1
Formulas

• Unit 6 - Bonding

2
Formulas

• Chemical formula represents the type and number
  of atoms in the smallest representative unit of a
  compound
• Formula unit lowest whole number ratio of atoms
  in an ionic compound not a discreet molecule

3
Formulas

• Writing Formulas
• Binary Compounds compounds with 2 types of
  atoms
• Examples NaCl, MgO, Al2O3

4
Formulas

• Method for Writing Binary Compounds Formulas
• Writing the elements as ions
• Positive goes first!!
• Cross the value of the charge to subscripts
• MAKE THE CHARGE ZERO!
• Reduce when necessary

5
Formulas

• Transition metals ? The Exception
• Have more than one valence
• The charge is given as a Roman numeral in
  parenthesis after the word.

6

• Sodium chloride
• Magnesium sulfide
• Calcium iodide
• Lithium sulfide
• Aluminum oxide
• Magnesium phosphide
• Lead (IV) chloride

7
Formulas

• Ternary Compounds compounds with more than 2
  types of atoms
• Contains polyatomic ions a group of elements
  with a charge (back of periodic table)

8
Formulas

• Method for Ternary Compounds
• Write the ions out
• Put the positive ion first
• Cross the charges to subscripts
• Keep the polyatomic ions together!

9

• Sodium hydroxide
• Potassium sulfite
• Aluminum carbonate