(4.8) Polar Bonds and Molecules

Explain Explain this statement: Not every molecule with polar bonds is polar. Use

The atoms in CCl4 baseline are oriented so that the bond polarities cancel.

Explain How do electronegativity values determine the charge distribution in a polar covalent bond?

The more electronegative atom attracts electrons more strongly and gains a partial negative change. The less electronegative atom has a partial positive charge.

What happens when polar molecules are between oppositely charged metal plates?

They bend because of the negative force. Answer: Polar molecules tend to become oriented with respect to the positive and negative plates.

Compare How does a network solid differ from most other covalent compounds?

Network solid are covalent compounds. Answer: The atoms in a network solid are covalently bonded in a large array (or crystal) which can be thought of as a single molecule.

Draw Draw the electron dot structure for each molecule. Identify polar covalent bonds by assigning slightly positive (δ+) and slightly negative (δ-) symbols to the appropriate atoms.

H(δ+) O(δ-) O(δ-) H(δ+) Br(δ+) Cl(δ-) Br(δ-) H(δ+) H(δ+) O(δ-) H(δ+)

Compare How do the strengths of intermolecular attractions compare to the strengths of ionic bonds and covalent bonds?

Intermolecular attractions are weaker than either ionic or covalent bonds.

Explain Why are the properties of covalent compounds so diverse?

Melting a network solid requires breaking covalent bonds throughout the solid.