ch 1- atoms, elements and the periodic table Flashcards
atom
smallest unit of matter used in VCE chemistry
atomic number
number of protons in the nucleus of an atom
chemical symbol
abbreviation used to represent a chemical element
compound
two or more atoms of different elements bound together
electron
negatively charged particle that exists outside the nucleus of an atom
element
pure substance containing only a single type of atom
ion
atom that has lost or gained electrons to become a charged particle
isotope
variants of an element which have the same atomic number but a different number of neutrons in their nuclei
mass number
mass of an atom, equal to the sum of protons and neutrons
molecule
when two or more non-metal atoms bond by sharing electrons
neutron
neutral particle inside the nucleus of an atom
nucleus
region at the centre of an atom that contains protons and neutrons
periodic table
table of chemical elements in which elements are arranged in order of increasing atomic number
proton
positively charged particle inside the nucleus of an atom
subatomic particle
particle that exists inside the atom
Aufbau principle
rule that states subshells are filled by electrons from the lowest
to the highest energy level
blocks
assortment of elements into discrete categories based on which subshell their valence electrons are found in
electron configuration
arrangement of electrons in shells and/or subshells
energy shells/energy levels
orbits containing different levels of energy, around the nucleus of an atom where electrons are found according to the Bohr
and Schrodinger models
groups
columns in the periodic table
orbitals
regions with the highest probability of finding electrons
pauli exclusion principle
rule that states an orbital can’t hold more than 2 electrons
periods
rows in the periodic table
periodicity
characteristics of elements in a period