4: Ionic Compounds Flashcards
Features of ionic bonding model
Metals donate valence electrons to form cations
Non metals gain e- to make anions
Electrostatic force of attraction between cations and anions
Ionic compounds (salts) have a neutral charge
Solid salts have a 3D symmetrical crystal lattice
Why are cations (Na+) drawn smaller than their neutral atoms (Na)?
Because cations donate their valence electrons to bond, they also decrease in atomic radius
Why are cations (Cl-) drawn smaller than their neutral atoms (Cl)?
Because anions gain electrons, the repulsion between the electrons increases, increasing the anion’s size
Why do ionic compounds have high melting/boiling points?
- Strong ionic bonding between cations and anions
- A lot of energy is required to break these bonds
- Hence, high mp and bp
Why are ionic compounds brittle and hard?
- Cations and anions are held in fixed positions in Ionic compounds
- When a force is applied, like charges are pushed together and repel,
- Lattice shatters
Why can’t ionic compounds conduct electricity IN THE SOLID STATE?
- Electrical conductivity requires free moving charged particles
- Because cations and anions are kept in fixed positions, therefore they can’t conduct electricity
Why can ionic compounds conduct electricity IN THE LIQUID/AQUEOUS STATE?
- Electrical conductivity requires free moving charged particles
- Ions can move around in the liquid/aqueous state
- hence can conduct electricity
Ionic equations
ONLY shows the reaction for the precipitate
Spectator ions
Ions that DO NOT PARTICIPATE in the reaction
Things to show in ionic equations
Charges of reactants
States of reactants and products
