Glossary:
| Term | Definition | Relevant Topics |
|---|---|---|
| Activation Energy | Activation energy is the minimum energy required for reactants to undergo a chemical reaction. It can be lowered by using a catalyst. | Thermochemistry |
| Anion | A negatively charged ion. Anions are attracted to the anode (positive electrode) during electrolysis. | Electrolysis |
| Anode | The positive electrode. | Electrolysis |
| Bond Energy | Bond energy is the amount of energy required to break one mole of a stated bond, measured in kJ/mol. It can be used to calculate ΔH for a reaction. | Thermochemistry |
| Cathode | The negative electrode. | Electrolysis |
| Cation | A positively charged ion. Cations are attracted to the cathode (negative electrode) during electrolysis. | Electrolysis |
| Compound | Two or more elements that are chemically joined. | Structure & Bonding |
| Covalent Bond | A shared pair of electrons. | Structure & Bonding |
| Covalent Bonding | The electrostatic forces of attraction between a shared pair of electrons and common nuclei. | Structure & Bonding |
| Electrode | A solid electrical conductor that connects the power source to the electrolyte. Graphite is a common electrode material as it conducts electricity and is chemically inert. | Electrolysis |
| Electrolysis | Chemical change caused by passing an electric current through an electrolyte. | Electrolysis |
| Electrolyte | A solution or molten substance that conducts electricity. When a current is passed through an electrolyte, electrolysis takes place. | Electrolysis |
| Element | A chemical made of only one type of atom. | Structure & Bonding |
| Empirical Formula | The empirical formula of a compound is the simplest positive integer (whole number) ratio of atoms of each element in that compound. | Moles |
| Endothermic Reaction | An endothermic reaction is one which takes in energy from the surroundings, usually in the form of heat and usually shown by a fall in temperature. | Thermochemistry |
| Exothermic Reaction | An exothermic reaction is one which gives out energy to the surroundings, usually in the form of heat and usually shown by a rise in temperature. | Thermochemistry |
| Ion | A charged particle that has lost or gained electrons. | Structure & Bonding |
| Ion Migration | The movement of ions from the electrolyte to the electrodes (anode and cathode) when an electrical current is passed through it. | Electrolysis |
| Ionic Bonding | The electrostatic forces of attraction which hold positive and negative ions together in an ionic lattice. | Structure & Bonding |
| Isotope | Isotopes are atoms that have the same number of protons but different numbers of neutrons. They consequently have the same atomic number, but differ in mass number. | Moles |
| Lattice | A regular, repeating, giant structure. | Structure & Bonding |
| Metallic Bonding | The electrostatic forces of attraction which hold positive ions and delocalised electrons together in a metallic lattice. | Structure & Bonding |
| Mixture | A material made up of two or more substances physically combined, but not chemically bonded together. | Structure & Bonding |
| Mole | A mole is the unit of 'amount of substance' (just as the gram is the unit of mass). 1 mole is the amount of substance that contains 6 x 1023 particles of the substance. It provides the link between the mass of a substance and the number of particles it contains. 1 mole of any particle has a mass equal to its Ar, in grams. | Moles |
| Molecule | Two or more atoms bonded covalently. | Structure & Bonding |
| REDOX Reaction | A reaction in which both oxidation and reduction take place. | Electrolysis |
| Relative Atomic Mass, Ar | The relative atomic mass is the average mass of an atom of an element compared to 1/12th the mass of a carbon-12 atom, taking into account the proportion of each isotope of the element present. | Moles |
| Relative Molecular Mass / Relative Formula Mass, Mr | The relative molecular mass is simply the sum of the relative atomic masses of the compound (or element, e.g. O2 = 2 x 16 = 32). | Moles |
| Salt | An ionic compound. | Structure & Bonding |
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