definitions

• Proton number

  The number of protons in the nucleus of an atom
• Nucleon number

  The total number of protons and neutrons in the nucleus
• Isotopes

  Atoms of the same element that have the same proton number and electron number but different nucleon number, meaning they have different numbers of nucleons
• Relative atomic mass

  The average mass of one atom of that element relative to 1/12 the mass of an atom of carbon-12
• Relative molecular mass

  The average mass of one molecule of that substance relative to 1/12 the mass of an atom of carbon-12
• Mole (in terms of Avogadro constant)


  One mole of any substance will always contain 6.02 × 10²3 particles of that substance. The particle can be atoms, molecules, ions and even sub-atomic particles such as electrons
• Acids

  A substance that produces hydrogen ions, H+, in aqueous solutions
• Alkali

  Any metal oxide or hydroxide. They contain either the oxide ion, O ²-, or the hydroxide ion, OH- and are soluble in water
• Oxidation (in terms of oxygen/ hydrogen)

  The gain of oxygen/ loss of hydrogen
• Reduction (in terms of oxygen/ hydrogen)

  The opposite of oxidation and can be defined as the loss of oxygen/ gain of hydrogen
• Redox (in terms of oxygen/ hydrogen/ electron)

  When there is a gain of oxygen or loss in hydrogen or loss of electrons, indicating oxidation, and there is a loss in oxygen or gain in hydrogen or gain of electrons, indicating reduction
• Catalyst

  They increase the rate of chemical reactions without being chemically changed at the end of the reaction by providing an alternative pathway of lower activation energy for the reaction to occur. This hence, speeds up the rate of reaction
• Isomerism

  The phenomenon where 2 or more compounds have identical molecular formula but possesses different structural formulae, and consequently different properties
• Polyunsaturated


  Polyunsaturated fats contain hydrocarbon chains with 2 or more carbon-carbon double bonds in each chain