Covalent Bonds

Review Questions

Multiple Choice

What formula results when Ca⁺²  and  Br^- ions bond?

• Ca₂Br₂
• CaBr
• Ca(br)₂
• CaBr₂

Multiple Choice

What is the formula for calcium carbonate?

• CaCO

• CaCO₂

• CaCO₃

• Ca₃CO₃

Multiple Choice

The proper formula for magnesium hydroxide:

• MgOH
• Mg₂OH
• Mg(OH)₂
• Mg₂OH₂

Covalent Bonds

We Will:

1. Overview Covalent Bonds

2. Lewis Structural Formulas for Molecular Bonding

3. Single, Double, and Triple Covalent Bonding

   
   

​I will:
Practice and Apply what I have learned

Covalent Bonds Octet

Sharing electrons to fill the octet

• Polar Covalent bond (nonmetal-nonmetal)

  • unequal sharing of electrons

    • stronger electronegative atom

• Nonpolar Covalent Bond (nonmetal-nonmetal)

  • equal sharing of electrons

Multiple Choice

Are diatomic atoms (O₂, H₂. N₂, Cl₂) polar or nonpolar? (use your electronegativity table)

• Polar

• Nonpolar

Nonmetal-Nonmetal Covalent Bond

Physical Properties

• Low melting point

• Usually, they are gasses, liquids, or waxy.

• Do not conduct electricity.

Multiple Choice

In solution, ionic bonds dissociate, forming ions that can conduct electricity, which bond type is not a good conductor of electricity?

• covalent

• metallic

Lewis/ Structural Formulas for Molecular Bonding

​Electron pair bonds (atoms share one or more valence electrons)

*Octet Rule (stable atoms desire a filled shell of 8)

• A dash or line represents shared electrons.

• Dots represent lone pairs (non-bonded) electrons.
  

​Lone pairs

​Bonded

Draw

Draw the Structural Formula for (diatomic oxygen) Br₂

Single, Double, and Triple Covalent Bonding

Atoms can share one or more pairs of electrons

• Single Bonds

  • Share a single pair of electrons and have a single dash/line representing the paired electrons

• Double Bonds

  • Share two sets (pairs) of electrons and have a double dash/line representing the paired electrons.

• Triple Bonds

  • Share three sets (pairs) ...

Multiple Choice

Oxygen is a diatomic element which means in nature, it is found in two's. (O₂) Oxygen shares two pairs of electrons to make sure each atom completes the octet rule. This creates a...

• single bond

• double bond

• triple bond

Bond Length and Strength

• Triple Bonds

  • are the strongest and shortest

• Double Bonds

  • are in the middle

• Triple Bonds

  • are weaker than the triple and double bonds

​Energy is needed to break bonds—the more bonds, the more energy is required to separate atoms.

Match

Match the covalent bond types.

• Hydrogen

• Oxygen

• Nitrogen

Single Bond

Double Bond

Triple Bond

• Single Bond

• Double Bond

• Triple Bond

Coordination Chemistry

A chemical compound with a central atom surrounded by other atoms.

• Central atom often has the lowest electronegativity.

• The central atom has the least number of electrons