Unit 3 Part 1 - 2.1 The Ionic Model Flashcards
12APR25
Why are valence electrons more open to external influences?
Because they are furthest from the electrostatic attraction of the nucleus
What do valence electrons of metal atoms experience?
Smaller Zeff than non-metal valence electrons
Why are valence electrons not involved in the charge number?
Because they are shielded from the nucleus and repelled by inner electrons
What does the presence of the inner electrons do?
Reduce the attraction of the nucleus for the outer electrons
Why is the full attractive force of the nucleus not felt by the outer electrons?
- Distance from the nucleus
- Electrons are at higher energy levels resulting in less electrostatic force - Shielding
- Inner electrons which have lower energy levels repel outer electrons b/c they have like charges
Why is atomic radius larger as we descend a column?
Down a column:
1.Electrons are further from the nucleus in higher energy levels
2. As the energy level increases the boundary surface (edge of orbital) is further
3. Increasing the number of shielding electrons inside
Why do ionic compounds form lattice structures?
B/c they are rarely in isolation
Why does phosphorus form ionic compounds less readily than chlorine and sulfur?
B/c it’s outer electrons only experience a Zeff of +5
Why does chromium have a max oxidation state at +6?
B/c there is a big jump in ionization energies when the 7th electron is removed
Why does manganese have a max oxidation state at +7?
B/c there is a large jump in ionization energy with the removal of the 8th electron
What kind of bonding is within the polyatomic ion?
Covalent
Features of a 3D lattice structure?
- Fixed arrangement of unit cells
- Can be infinite (repeating pattern)
- Empirical formula = formula unit
What does the lattice structure result in?
Ionic compounds being crystalline solids at room temp
Why do ionic compounds have high melting and boiling points?
B/c a large amount of energy is needed to separate the ions in the lattice
When are melting points generally higher?
When the ionic charge is greater due to increased strength of the ionic bond
What is volatility?
How easily a chemical can evaporate
What kind of volatility do ionic compounds have?
Low
Why does an increase in ionic radius for halides mean lower melting point?
B/c the attraction between the ions decrease
What are some ionic properties?
- Brittle
- Electricity conduction when dissolved in water
- Soluble in water (polar solvents)
Why are ions brittle?
B/c when force is applied some ions are displaced causing them to be beside another similar ion which causes more repulsion and lattice splits
Why can ions conduct electricity only when they are dissolved in water or in the molten state?
B/c they can move
Why can solids not conduct electricity?
B/c there’s no movement of electrons in the lattice structure
Every bond has how many electrons?
2
When is it a covalent bond?
When electrons are equally shared
- two non-metals
