Chemistry essential terms

Atom

the smallest possible particle of an element; atoms are made up of protons, neutrons and electrons

Chemical bond

a strong electrostatic force of attraction

Compound

a pure substance made of two or more different elements whose atoms are joined by chemical bonds; the atoms are in a fixed ratio

Conductor of electricity

a substance that allows charged particles to move through it easily

Dot and cross diagrams

used to show how electrons from the outer shells/energy levels of atoms are shared or transferred when atoms form molecules or Ions

Electron

a negatively charged subatomic particle with very little mass found in the electron shells/energy levels of atoms

Electron shell

a region surrounding the nucleus of an atom where electrons are found; each level has a maximum number of electrons it can hold

Element

a pure substance made of only one type of atom

Giant lattice

the regular arrangement of atoms or ions that form extended structures

Inelastic

Is not flexible

Regular lattice

an arrangement of repeating atoms or ions that form a 3D structure

Subatomic particle

a particle smaller than an atom

Covalent bond

a type of bond formed by atoms sharing one or more pairs of electrons

Diatomic

when a molecule is composed of two atoms

Intermolecular forces

the attractive and repulsive forces within a molecule

Macromolecule

a very large molecule

Molecule

two or more atoms connected by chemical bonds

Anion

a negative ion

Brittle

something that cracks or breaks when force is applied to it

Ion

a charged particle formed when one or more electrons are lost or gained from an atom or molecule

Ionic bond

an electrostatic force of attraction between oppositely charged ions in a regular lattice that forms between a metal and a non-metal

Polyatomic ion

a charged particle made of two or more atoms joined together

Alloy

a mixture of two or more elements at least one of which is a metal, where the resulting mixture has metallic properties

Cation

a positive ion

Delocalised electron

an electron in a molecule or structure that is not associated with any particular atom, ion, or covalent bond and which is free to move

Ductile

can be drawn out into wires

Electrostatic force of attraction

a force of attraction between particles with opposite charges

Malleable

can be hammered or bent into shape

Metal

an element that is shiny when cut, malleable and conducts electricity well; metals are found on the left and middle of the periodic table and tend to lose electrons to form positive ions

Metallic bond

an electrostatic force of attraction between delocalised electrons and the positive ions in a regular lattice

Thermal conductivity

a measure of how easily a substance allows heat to move through it

Allotropes

different forms of the same element in the same physical state; for example, allotropes of carbon are diamond, graphite, graphene and fullerenes

Tetrahedral

molecules and structures that have one atom in the centre and four atoms at the corners of a triangular pyramid