Unit 1a. EM Radiation & Atomic Spectra Flashcards
1
Q
What is electromagnetic radiation?
A
Waves that have both wavelength and frequency.
2
Q
What is wavelength ?
A
The distance between 2 wave crests
3
Q
Photons and frequency
A
- Photons have quantised energy proportional to the frequency of the radiation
- Higher frequency = higher energy
4
Q
Photons and wavelength
A
- Photons have quantised energy inversely proportional to the wavelength of the radiation
- Lower wavelength = higher energy
5
Q
Photons and electrons
A
- When a photon is absorbed, electrons can gain energy and be promoted to a higher energy level. ( An “excited” electron)
- When a photon is emitted by an excited electron, it will lose energy and drop to a lower energy level.
6
Q
Recognising absorption and emission line spectra
A
- absorption spectra show black gaps or lines
- emission spectra show different coloured lines in the spectra.
7
Q
What do photons carry?
A
Quantised energy
- proportional to the frequency of the radiation
- inversely proportional to the wavelength of the radiation
8
Q
A
9
Q
A
Heat / High temperatures
10
Q
A
11
Q
A
12
Q
A
Different electron transitions between different energy levels.
