Periodic Table Flashcards
Element
Substances that cannot be split into simpler substances by chemical means
Dobereiners triads
Groups of 3 elements with similar chemical properties where the atomic weight of the middle one is equal to the average of the other two elements
Newlands octaves
Increasing atomic weight , first element and the 8th element have similar chemical properties
Mendeleev periodic table
Arranged by atomic weight
Atomic number
Number of protons
Modern periodic law
Arranged by atomic number
Mass number
Number of protons and neutrons
Isotopes
Atoms of the same element but with different atomic mass due to the different number of neutrons in a nucleus
Relative atomic mass
The average mass of the isotope of an element taking into account their natural abundances compared to 1/12 of the mass of a C-12 isotope
Mass spectrometer
Vaporisation, ionisation, separation , acceleration, detection
Aufbau principle
The building up of electron configuration, the electrons take up the lowest energy level
Hunds rule of maximum multiplicity
When two or more orbitals of equal energy are available the electrons occupy them singly before filling in pairs
Pauli exclusion principle
No more than 2 electrons may occupy an orbital that must have an opposite spin
Atomic radius
Half the distance between the nuclei of two atoms of the same element that are joined together by a single covalent bond
First ionisation level
The angry required to remove the most loosely bound electron from a neutral gaseous atom
