Activation energy ($E_a$) is the minimum amount of energy that reacting particles must have for a chemical reaction to start.

Measured mass or amount of product actually obtained from a chemical reaction in an experiment. This is usually less than the calculated maximum (theoretical yield) due to incomplete reactions or material loss during processes like filtering or transferring

Organic compounds that contain one or more hydroxyl groups (–OH) attached to a carbon atom in a hydrocarbon chain.

Hydrocarbons (compounds made only of carbon and hydrogen), which contain only single bonds between carbon atoms (C–C)

Hydrocarbons that contain at least one carbon–carbon double bond (C=C).

1 atomic mass unit (1 u) is defined as one-twelfth of the mass of a carbon-12 atom.

It defines which element the atom is by indicating the number of protons in the nucleus.

For a fixed amount of gas at constant temperature, pressure is inversely proportional to volume.

Charles’s Law describes how the volume of a gas changes with temperature when pressure is constant.

Symbolic representation showing the elements in a substance and their numbers or ratios.

Separates components of a mixture based on (1) their solubility in a mobile phase (e.g. solvent) and (2) their adsorption (attraction/attachment) to a stationary phase (e.g. paper).

A colloid is a mixture where particles are larger than in a solution, but still small enough to remain dispersed and not settle quickly.

It describes how much a substance can decrease in volume when external pressure is applied.

The number of coordinate bonds formed between the central metal ion and the ligands.

Corrosion is a slow, continuous deterioration of metals caused by reactions with substances in the environment, such as oxygen, water, acids, salts (electrolytes).

Occurs between non-metal atoms that share electrons so each achieves a full outer shell.

Forms when non-metal atoms share electrons. It may form small molecules (like $CO_2$) or giant covalent structures (like diamond).

It explains how much matter is packed into a certain volume.

Diffusion is the net movement of particles from an area of higher concentration to an area of lower concentration.

The process in which particles spread from regions of high concentration to regions of low concentration.

A displacement reaction happens when a more reactive metal displaces a less reactive metal from one of its compounds (usually a solution of a salt).

Separates liquids (or a liquid from dissolved solids) using differences in boiling point.

A simple electrochemical cell (also called a voltaic or galvanic cell) converts chemical energy from a spontaneous redox reaction into electrical energy.

It describes the arrangement of an atom’s electrons in its energy levels, sublevels and orbitals.

The ability of an atom to attract a bonding pair of electrons in a covalent bond.

Shows the simplest whole-number ratio of atoms in a compound.

An endothermic reaction is a reaction that absorbs energy (usually heat) from its surroundings.

A measure of the total heat content of a system at constant pressure.

An exothermic reaction is a reaction that releases energy (usually heat) into the surroundings.

Extraction is the process of obtaining a relatively pure substance from a mixture or compound using physical or chemical methods.

A technique used to separate an insoluble solid from a liquid in a mixture (e.g. a suspension).

For a fixed amount of gas at constant volume, pressure is directly proportional to temperature (in Kelvin).

Green chemistry is an approach where chemists design products and processes to minimize environmental impact.

The group number of a main-group element indicates the number of valence electrons (electrons in the outermost energy level).

Occurs when electrons are transferred from a metal atom to a non-metal atom.

Formed from positive and negative ions (usually metal + non-metal, or metal + polyatomic ion) held together in a giant ionic lattice.

Ionisation energy is the energy required to remove one mole of electrons from one mole of gaseous atoms.

Atoms of the same element (same protons/atomic number) that have different numbers of neutrons, resulting in different mass numbers

Latent heat is the energy absorbed or released without a change in temperature while a substance changes state.

Energy required to change 1 kg (or 1 mole) of a substance from solid to liquid at constant temperature.

Energy required to change 1 kg (or 1 mole) of a substance from liquid to gas at constant temperature.

A ligand is a species (ion or molecule) that donates a lone pair of electrons to the central metal ion, forming a coordinate (dative) covalent bond.

Substance in a chemical reaction that gets completely used up first, thereby "limiting" or stopping the reaction and determining the maximum amount of product that can be formed, with any leftover reactants being in excess.

The total number of protons and neutrons in the nucleus.

The amount of substance that contains $N_A=6.022×10^{23}$ particles (atoms, molecules, ions, etc.).

Shows the actual number of each type of atom in a single molecule (common for covalent substances).

A solution is neutral if $\left[\mathrm{H}^{+}\right]=\left[\mathrm{OH}^{-}\right]$ and its pH = 7.

Neutralization is the reaction in which hydrogen ions (H⁺) from an acid react with hydroxide ions (OH⁻) from a base to form water.

A region of space around the nucleus where there is a high probability of finding an electron.

Ratio of the actual yield (product obtained in an experiment) to the theoretical yield (maximum possible product from stoichiometry), expressed as a percentage, showing reaction efficiency.

$$\% \text { yield }=\frac{\text { actual yield }}{\text { theoretical yield }} \times 100$$

The period number of an element tells you the highest principal energy level (n) that contains electrons.

A polyatomic ion is a group of atoms bonded together that carries an overall charge and behaves as one unit in ionic compounds.

The weighted average mass of all the atoms (isotopes) of that element in a sample, relative to 1/12 of the mass of a carbon-12 atom.

Simple oxidation is a reaction where a metal reacts with oxygen and forms a thin oxide layer on its surface.

A solution is a homogeneous mixture where the particles of the solute are completely dissolved in the solvent.

A suspension is a heterogeneous mixture with large particles that are temporarily suspended in a liquid or gas.

The maximum possible amount of product, calculated from the limiting reactant (assuming the reaction goes to completion with no losses).

A titration is a technique used to find the concentration of an unknown solution by reacting it with a solution of known concentration.

An element that forms at least one ion with a partially filled d-subshell.