Zusammenfassung der Ressource
Electron arrangements
- Energy levels
- Electrons in different shells have differing amounts of energy
- Shells are called main energy levels
- Divided into sub-levels
- S sublevel
- Can hold 2 electrons
- Spherical
- P sublevels
- Can hold 6 electrons
- 3 dumbell shape
- D sublevel
- Can hold 10 electrons
- 5 dumbell shape
- F sublevel
- Quantum mechanics
- Developed 1920's
- Schrodinger equation
- Give the probability of finding an electron in a given volume of space called an atomic orbital
- Atomic orbitals
- Electron
- Cloud of negative charge
- Fills volume known as its atomic orbital
- Concept
- Different orbitals = different energies
- Number tells us which energy level it corresponds to
- Atomic orbitals of each main level have different shapes which have slightly different energies
- Shapes of orbitals represent a volume of space in which there is a 95% probability of finding an electron
- First main energy level consists of just one s orbital, the second has an s and a p,
- Any atomic orbital can hold 2 electrons
- S orbitals can hold up to two electrons
- P orbitals can hold 2 each, but come in groups of 3
- D orbitals can hold 2 each, but come in groups of 5
- Spin
- Electrons have a property called spin
- 2 electrons in the same orbital must have opposite spin
- This creates a magnetic attraction between the two, allowing them to sit in the orbital without repulsion
- Electrons are usually represented by arrows pointing up or down to show different directions of spin
- Repulsion
- Has to be some sort of attraction to hold e- in an orbital
- Order of filling
- Aufbau principle
- Lower energy orbitals filled first
- No atomic orbital can hold more than 2 electrons
- 4s fills before 3d
- Hunts rule
- FIll singly before pairing
- Opposite number of spins minimised