Chapter 5 - Electrons and bonding Flashcards
Define ‘Shells’
A group of atomic orbitals that which have the same value of the principle quantum number
What are the names for the 4 sub-shells?
S P D F
What are electrons held in?
Clouds of negative charge (orbitals)
Define ‘ Orbitals’
A region around the nucleus that can hold up to two electrons with opposite spins
How many electrons can an S orbital hold?
2 electrons
How many electrons can a P orbital hold?
6 electrons
How many electrons can a D orbital hold?
10 electrons
How many electrons can a F orbital hold?
14 electrons
What is the shape of an S orbital?
Shaped like a sphere
What is the shape of a P orbital?
Shaped like a dumb-bell
Define ‘Ionic Bonding’
The electrostatic attraction between positive and negative ions formed by electron transfer and form a giant ionic lattice
What state are all ionic compounds at room temperature?
Solid
Why do ionic compounds have high boiling and melting points?
- Ionic compounds contain strong electrostatic forces of attraction between oppositely charged ions that hold the giant lattice together
- This requires high temperatures to provide large quantities of energy needed to overcome these forces.
Why do ionic compounds dissolve in polar solvents?
Polar molecules can break down the giant ionic lattice and surround each ion in the solution
What can an ionic compound not conduct electricity?
- In the solid state, the ions are in a fixed position in the giant ionic lattice
- This means that they do not contain delocalised electrons are not free to move and carry charge through the structure
Why can an ionic compound when molten or dissolved in aqueous conduct electricity?
- When dissolved in aqueous solution or in the molten state, ions are no longer held in the lattice and are free to move
- These delocalised electrons can carry charge through the structure and conduct electricity
Define ‘Covalent Bonding’
The strong electrostatic attraction between a shared pair of electrons and the nuclei of the bonded atoms formed between 2 non-metals
How many covalent bonds can carbon form?
4 bonds
How many covalent bonds can nitrogen form?
3 bonds
How many covalent bonds can oxygen form?
2 bonds
How many covalent bonds can hydrogen form?
1 bond
What happens in double covalent bonds?
The electrostatic attraction between two shared pairs of electrons and the nuclei of the bonding atoms
What happens in triple covalent bonds?
The electrostatic attraction between three shared pairs of electrons and the nuclei of the bonding atoms
Define a ‘Dative covalent bond’
Formed when the shared pair of electrons in the covalent bond come from only one of the bonding atoms
