Molecular Compounds

1
Molecular Compounds

• Chapter 8.1 and 9.3

2
Learning Objectives

• Basic understanding of covalent compounds and
  their properties
• Understand basics of a molecular formula
• How to name covalent compounds

3
Molecular Compounds

• Compounds made from nonmetals are called
  molecular or covalent compounds
• Occurs when two or more elements share electrons
  to achieve stable octets
• Held together by covalent bonds (we will talk
  about this next lecture)

4
Molecular Compounds

• Properties of molecular compounds
• Low melting and boiling points
• Exist as gases or liquids at RT
• Made of nonmetals
• Neutral compounds can gain a unit charge to
  become polyatomic ions

5
Molecular Formula

• Molecular compounds are written as molecular
  formulas
• Examples
• CO2 means 1 atom of C and 2 atoms of O
• H2O means 2 atoms of H and 1 atom of O

6
Naming Molecular Compounds

• First element is named using standard name
• Second element prefixes are used to denote the
  number of atoms present
• named with an ide ending
• But dont use mono on the first element
• Mono 1 Di 2 Tri 3 Tetra 4 Penta 5
• Hexa 6 Hepta 7 Octa 8 Nona 9 Deca 10

7
Homework

• Read Chapters 8.1,8.2, and 9.3.
• 8.1
• Page 216 1-4
• Page 247 39-41
• 9.3
• Page 270 22-25