Chemistry SPM Form 5 Definitions of Terms

Comprehensive vocabulary flashcards covering the key terms and standard definitions for SPM Form 5 Chemistry across Chapters 1 to 5.

Redox reaction

Chemical reaction where oxidation and reduction occur simultaneously.

Standard electrode potential

Potential difference produced when an equilibrium is established between metal M and the aqueous solution containing metal $M^{n+}$ ions in a half-cell.

Electrolyte

Substances that can conduct electricity in either molten state or aqueous solution and undergo chemical changes.

Non-electrolyte

Substances that cannot conduct electricity in all states.

Conductor

Substances that conduct electricity in solid or molten state but do not undergo chemical changes.

Electrolysis

Process whereby compound in the molten or an aqueous solution decompose into their constituent elements by passing electricity through them.

Anode

An electrode where oxidation reaction occurs.

Cathode

An electrode where reduction reaction occurs.

Corrosion of metal

Redox reaction where the metal is oxidised spontaneously when the metal atoms release electrons to form metal ions.

Carbon compounds

Compounds that contain carbon as their constituent element.

Organic compounds

Compounds that originating from living things that contain carbon element bonded covalently with other elements such as hydrogen, nitrogen, sulphur and phosphorus.

Inorganic compounds

Compounds that originating from non-living materials such as oxides of carbon, carbonate compounds and cyanide compounds.

Hydrocarbon

Compound that containing only hydrogen and carbon.

Non hydrocarbon

Compound that containing carbon and hydrogen and other elements such as oxygen, nitrogen, phosphorus or halogens.

Saturated hydrocarbon

Hydrocarbon containing only single bonds between carbon atoms.

Unsaturated hydrocarbon

Hydrocarbon containing at least one double bond or triple bond between carbon atoms.

Cracking

Process of breaking long chain hydrocarbons into smaller molecules.

Isomers

Molecules that have same molecular formula but different structural formulae.

Exothermic

Chemical reaction that releases heat to the surroundings.

Endothermic

Chemical reaction that absorbs heat from the surroundings.

Heat of Reaction

Heat change of one mole of reactant that reacts or one mole of product that is formed.

Heat of Precipitation

Heat change when $1\text{ mole}$ of precipitate is formed from their ions in an aqueous solution.

Heat of Displacement

Heat change when $1\text{ mole}$ of a metal is displaced from its salt solution by a more electropositive metal.

Heat of Neutralisation

Heat change when $1\text{ mole}$ of water is formed from the reaction between an acid and an alkali.

Heat of Combustion

Heat released when $1\text{ mole}$ of a substance is completely burnt in excess oxygen.

Heat of Combustion of alcohol

Heat released when $1\text{ mole}$ of an alcohol is completely burnt in excess oxygen.

Fuel value

Amount of heat energy released when $1\,\text{g}$ of fuel is completely burnt in excess oxygen.

Polymers

Long chain molecule that is made from a combination of many repeating basic units called monomers.

Vulcanisation

A process of producing rubber that is more elastic and with better quality through the production of cross-links between polymer chains.

Synthetic rubber

Synthetic polymer that is elastic in nature or elastomer polymer.

Saturated fat

Fat that contains saturated fatty acids.

Unsaturated fat

Fat that contains unsaturated fatty acids.

Soap

Sodium or potassium salts of long chain fatty acid.

Detergent

Sodium salts of sulphonic acids.

Food additive

Natural or synthetic ingredients added to food to prevent damage or to improve the appearance, taste or texture.

Medicines

Chemicals used to help with the treatment or prevention of diseases.

Cosmetics

Materials or products that are used externally to cleanse, protect or enhance one’s appearances.

Nanoscience

A study on processing of substances at nanoscale that are between $1\,\text{nanometre}$ to $100\,\text{nanometres}$.

Nanotechnology

Development of substances or gadgets using the properties of nanoparticles.

Green Technology

Technology or application developed to minimise the negative effects of harmful human activities.