Chem unit 2 and 12

charlotteamannt's version from 2018-11-05 16:05


Question Answer
Atomsmallest particles that have the properties of an element
Nucleons particle in nucleus, two nucleons in the nucleus are protons and neutrons
atomic (or proton) numbnumber of protons in the nucleus of the atom
Mass numbernumber of protons + number of neutrons
Pauli exclusion principleAn atomic orbital can hold a maximum of two electrons
Aufbau principleelectrons fill atomic orbitals of lowest energy first
Hund's ruleelectrons fill orbitals in the same sub-level singly, before pairing up
Absorption line spectraproduced when electrons absorb energy and transition from lower to higher energy levels.
Emission line spectra produced when electrons emit energy and transition from higher to lower energy levels.
first ionisation energy (IE1) of an elementnergy required to remove one mole of electrons from one mole of gaseous atoms to produce one mole of gaseous 1+ ion