Chapter 6: ionic bonding

Question 1

How do noble gases differ from other elements?

Answer 1

Monoatomic, stable, unreactive.

Other elements combine with other atoms to form molecules and compounds.

Question 2

What is the electronic configuration of a noble gas?

Answer 2

They have fully filled outer shells and are stable.

Question 3

How do atoms achieve the electronic configuration of a noble gas?

Answer 3

Losing, gaining or sharing outer electrons, forming ions only when losing or gaining.

Question 4

What is an ion?

Answer 4

Electronically charged particle.

Cations: When atoms lose electrons (usually metals)

Anions: When atoms gain electrons (usually non-metals)

Question 5

Name the charges of silver, ammonium, zinc, aluminium and chromium

Answer 5

1+, 1+, 2+, 3+, 3+

Question 6

Name the charges of hydrogen carbonate, nitrate, carbonate, sulfate and phosphate

Answer 6

1-, 1-, 2-, 2-, 3-

Question 7

What are ionic bonds?

Answer 7

Strong electrostatic forces of attraction between positive and negative ions

Question 8

What is the structure of ionic compounds?

Answer 8

Giant lattice structure:

• Ions held in place by ionic bonds
• Packed in regular, repeating patterns
• Held together tightly because the opposite-charged ions attract each other strongly

Question 9

What are the physical properties of compounds?

Answer 9

1) Most have high melting/boiling points
- Forces of attraction between oppositely-charged ions are strong.
- Large amounts of heat energy are need to overcome these forces to melt the compound

2) Usually water-soluble, and insoluble in organic solvents
- Water molecules attract ions, weakening electrostatic forces between ions
- Ions are pulled from lattice-structure and the compound dissolves into an aqueous solution
- There’s no water in organic solvents, so ionic compounds remain tightly held in the lattice structure

3) Conduct electricity when molten/aqueous
- When ionic compounds melt/dissolve in water, cations and anions are free to move and conduct electricity
- No free-moving ions in solid state as ions are held in place in the lattice structure