anion
a negatively charged ion
atom
the smallest unit of an element that still retains the chemical properties of the element
atomic nucleus
the core of an atom that contains protons and neutrons
atomic number
the number of protons in an atom
atomic orbital
a region around the atomic nucleus where electrons are found
cation
a positively charged ion
chemical equilibrium
a state of balance in which forward and reverse chemical reactions are happening at the same rate
chemical reaction
a process that occurs when two or more atoms form chemical bonds or when chemical bonds between atoms break
chemical symbol
a one- or two-letter symbol used to identify an element on the periodic table
compound
a substance made of atoms of two or more elements bonded together in a certain ratio
covalent bond
a chemical bond that forms when atoms share electrons
electron
a negatively charged subatomic particle that moves in orbitals around the atomic nucleus
electronegativity
the tendency of an atom to attract electrons
element
a substance that cannot be broken down into simpler substances by chemical reactions
equilibrium constant
a number that expresses the relationship between the amounts of products and reactants present when a reversible chemical reaction is in balance
hydrogen bond
a weak bond between two molecules that results from an attraction between a proton in one molecule and an electronegative atom in the other
ion
a charged particle formed when an atom gains or loses electrons
ionic bond
a chemical bond that forms when valence electrons are transferred between atoms
London dispersion force
the weakest intermolecular force that forms due to attraction between molecules
mass number
a value that is equal to the number of protons and neutrons in an atom
matter
any substance that occupies space and has mass
molecule
a group of two or more atoms bonded together
neutron
a subatomic particle that has no charge
nonpolar covalent bond
a covalent bond that forms when two atoms share electrons equally
octet rule
a rule that states that atoms react by gaining or losing electrons in order to form the most stable electron valence structure
polar covalent bond
a covalent bond that forms from an unequal sharing of electrons between atoms
product
a substance formed as the result of a chemical reaction
proton
a subatomic particle that has a positive charge
reactant
a substance that reacts in a chemical reaction
valence shell
the outermost electron shell of an atom, where valence electrons are found