• Chemical Reaction: The breaking and making of bonds between different atoms to produce new substances are called reactions.
  • Chemical Equation: The representation of chemical reactions in the form of formulae of reactants and products separated by an arrow mark.
  • Balanced Equation: The same number of atoms of each element on the LHS (i.e, reactants) and RHS (i.e, products) of the equation.
  • Informative Equation: Representation of physical states using symbols like s (solid), l (liquid), g (gas), aq (water-soluble solutions), etc.
  • Combination Reaction: When two elements or one element and one compound or two compounds combine to give one single product.
  • Decomposition Reaction: Splitting of a compound into two or more simpler products.
  • Displacement Reaction: More reactive metal ( non–metal ) displaces the less reactive metal (non–metal ) and takes its place.
  • Oxidation Reaction: Reaction that involves the gain of oxygen or loss of hydrogen (loss of an electron.)
  • Reduction Reaction: Reaction that involves the loss of oxygen or gain of hydrogen (gain of electron).
  • Redox Reaction: Chemical reaction which shows both oxidation and reduction reaction.
  • Precipitation: The formation of insoluble compounds are called precipitate in a reaction.
  • Rancidity: Oils and fats gets oxidised when exposed to air show a change in smell and taste
  • Rusting: Iron reacts with oxygen and moisture and forms a reddish brown substance 
  • Corrosion: Metal when attacked by oxygen,water, acids or gases,present in the air change its surface.