Chapter 5 - Structure and Bonding Flashcards
What can an electron be thought of as ?
A negatively charged cloud with the shape of an orbital, called an electron cloud
Shells are regarded as what ?
Energy levels
What happens to energy as the shell number increases ?
Energy increases
What is the shell number referred to as ?
Principal quantum number (n)
What are shells made up of ?
Atomic orbitals
What is an orbital ?
- An orbital is an area around the nucleus where electrons with opposite spin are likely to be found
What are the different orbitals ?
- S orbitals
- P orbitals
- D orbitals
- F orbitals
How many electrons can be held in an orbital ?
One or two, no more
How many orbitals does each type contain ?
- S - one
- P - three
- D - five
- F - seven
How many electrons can be held in each type of orbital ?
- S - two
- P - six
- D - ten
- F - fourteen
What is the shape of an s orbital ?
Spherical
What is the shape of a p orbital ?
- Dumbbell
- Theres three types, one in each plane (x,y and z)
What are the rules of orbital fillings ?
- Orbitals fill in order of increasing energy
- Electrons pair with opposite spins
- Orbitals with the same energy are occupied singly first
Explain the rule of orbitals filling in order of increasing energy
- 1s is filled first
- Then 2s and 2p
- Then 3s, 3p, 4s and then 3d
Where does this rule cause confusion ?
- The 3d sub-shell has higher energy than the 4s.
- So the 4s fills before the 3d
State the orbital filling until the 4th shell
- 1s
- 2s, 2p
- 3s, 3p, 4s, 3d
- 4p, 4d, 4f
Explain the rule of electrons pair with opposite spins
- Electrons are negatively charged and repel one another
- Electrons can have spin up or spin down
- If electrons have opposite spin, the charge repulsion is counteracted enough for both to be in the orbital, they cancel out