e.g. nitrogen, alkanes, alkenes, polyalkenes, ethanol, propanol and isopropyl alcohol, iron, chlorine, zinc, nickel, copper, manganese, sodium…etc
e.g activated carbon, glucose, glycerol…etc.
e.g. oxygen, iron, magnesium, sodium and chlorine…etc.
e.g. acetic acid, fumaric acid, sodium hydroxide, potassium hydroxide,
sulphuric acid, hydrochloric acid…etc.
e.g. food colouring and food addictive
e.g. paracetamol, ibuprofen, diclofenac…etc.
e.g. reagents, indicators, buffer solution, stock solution….etc.