Chapter 6: ionic bonding Flashcards
How do noble gases differ from other elements?
Monoatomic, stable, unreactive.
Other elements combine with other atoms to form molecules and compounds.
What is the electronic configuration of a noble gas?
They have fully filled outer shells and are stable.
How do atoms achieve the electronic configuration of a noble gas?
Losing, gaining or sharing outer electrons, forming ions only when losing or gaining.
What is an ion?
Electronically charged particle.
Cations: When atoms lose electrons (usually metals)
Anions: When atoms gain electrons (usually non-metals)
Name the charges of silver, ammonium, zinc, aluminium and chromium
1+, 1+, 2+, 3+, 3+
Name the charges of hydrogen carbonate, nitrate, carbonate, sulfate and phosphate
1-, 1-, 2-, 2-, 3-
What are ionic bonds?
Strong electrostatic forces of attraction between positive and negative ions
What is the structure of ionic compounds?
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
What are the physical properties of compounds?
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
