Radiation with a wavelength longer than visible light but shorter than microwaves.
What is infrared radiation?
The equation that links photon energy to frequency.
What is E=hf?
The shape associated with an s‑orbital.
What is spherical?
The type of spectrum produced when excited electrons fall back to lower energy levels.
What is an emission spectrum?
The electron configuration of oxygen.
What is 1s² 2s² 2p⁴?
The relationship that links wavelength, frequency, and the speed of light.
What is c=λf?
A photon is a discrete packet — a quantum — of electromagnetic radiation energy.
What is a photon?
The number of p‑orbitals in a given energy level.
What is three?
The electron is promoted to a higher, quantised energy level.
What happens to an electron when an atom absorbs a photon of suitable energy?
The principle stating electrons occupy the lowest available energy level first.
What is the Aufbau principle?
The part of the EM spectrum responsible for electronic transitions in atoms.
What is visible/UV radiation?
The term for the minimum energy required to remove an electron from an atom.
What is ionisation energy?
The rule stating that electrons fill orbitals singly before pairing.
What is Hund’s rule?
A photon is emitted with energy equal to the energy difference between the two levels.
What happens when an excited electron falls from a higher energy level to a lower one?
The electron configuration of a Cu²⁺ ion.
What is [Ar] 3d⁹?
Increasing this property of EM radiation increases its energy.
What is frequency?
The energy of photons with wavelength 500 nm is approximately 239 kJ mol⁻¹.
What is the energy, in kJ mol⁻¹, of photons with wavelength 500 nm?
The quantum number that determines the shape of an orbital.
What is the angular momentum quantum number (l)?
Absorption spectra show selected wavelengths absorbed as electrons move to higher levels; emission spectra show selected wavelengths emitted as electrons fall to lower levels.
What is the difference between an absorption spectrum and an emission spectrum?
The principle that states no two electrons in one atom can have the same four quantum numbers; therefore an orbital holds a maximum of two electrons with opposite spins
What is the Pauli exclusion principle?
The region of the EM spectrum used to determine molecular bond vibrations.
What is infrared spectroscopy?
The constant that relates photon energy to frequency.
What is Planck’s constant?
The type of orbital that has a doughnut-shaped region of electron density.
What is a d‑orbital?
The reason each element produces a unique line spectrum.
What is unique electron energy levels?
Al loses a 3p electron, which is higher in energy and more shielded than Mg’s 3s electron, so less energy is needed to remove it.
Why is the first ionisation energy of aluminium lower than that of magnesium?