Common Chemical Compounds and Their Formulas

Chemical Formula – Key Facts

• A chemical formula represents the elements in a compound and the ratio of atoms
• Example: H₂O → 2 atoms of Hydrogen + 1 atom of Oxygen
• Subscripts → number of atoms
• Coefficients → number of molecules

Common Chemical Compounds and Their Formulas

1. Formula of Acids

• Hydrochloric Acid → HCl
• Sulphuric Acid → H₂SO₄
• Nitric Acid → HNO₃
• Carbonic Acid → H₂CO₃
•  Acetic Acid → CH₃COOH
•  Phosphoric Acid → H₃PO₄
•  Boric Acid → H₃BO₃
• Hydrofluoric Acid → HF
• Hydrobromic Acid → HBr

2. Formula of Basses

• Sodium Hydroxide (Caustic Soda) → NaOH
• Potassium Hydroxide (Caustic Potash) → KOH
• Calcium Hydroxide (Slaked Lime) → Ca(OH)₂
• Magnesium Hydroxide → Mg(OH)₂
• Barium Hydroxide → Ba(OH)₂
• Aluminium Hydroxide → Al(OH)₃
• Ferrous Hydroxide → Fe(OH)₂
•  Ferric Hydroxide → Fe(OH)₃
• Copper Hydroxide → Cu(OH)₂

3. Formula of Salts

• Sodium Chloride (Common Salt) → NaCl
• Potassium Nitrate (Saltpetre) → KNO₃
•  Copper Sulphate (Blue Vitriol) → CuSO₄·5H₂O
• Sodium Carbonate (Washing Soda) → Na₂CO₃·10H₂O
• Sodium Bicarbonate (Baking Soda) → NaHCO₃
• Calcium Carbonate (Marble/Limestone) → CaCO₃
• Ammonium Chloride (Sal Ammoniac) → NH₄Cl
• Magnesium Sulphate (Epsom Salt) → MgSO₄·7H₂O

4. Formula of Oxides

• Carbon Dioxide → CO₂
• Carbon Monoxide → CO
• Sulphur Dioxide → SO₂
• Sulphur Trioxide → SO₃
• Nitric Oxide → NO
• Nitrous Oxide (Laughing Gas) → N₂O
• Nitrogen Dioxide → NO₂
• Water?→ H₂O
• Ozone → O₃
• Hydrogen Peroxide → H₂O₂

5. Formula of Organic Compounds

• Methane (Marsh Gas) → CH₄
• Ethane → C₂H₆
• Propane → C₃H₈
• Butane → C₄H₁₀
• Ethylene (Ethene) → C₂H₄
• Acetylene (Ethyne) → C₂H₂
• Benzene → C₆H₆
•  Glucose → C₆H₁₂O₆
• Fructose → C₆H₁₂O₆
• Sucrose (Cane Sugar) → C₁₂H₂₂O₁₁

6. Formula of Industrial Compounds

• Bleaching Powder → CaOCl₂
• Plaster of Paris → CaSO₄·½H₂O
• Gypsum → CaSO₄·2H₂O
• Quicklime → CaO
• Slaked Lime → Ca(OH)₂
• Vinegar → Dilute CH₃COOH
• Borax → Na₂B₄O₇·10H₂O
• Alum (Potash Alum) → K₂SO₄·Al₂(SO₄)₃·24H₂O
• Common Glass → Na₂SiO₃ + CaSiO₃
• Silica (Quartz) → SiO₂

7. Formula of Elements & Simple Compounds

• Ammonia → NH₃
• Hydrogen Cyanide → HCN
• Phosphine → PH₃
• Hydrogen Sulphide → H₂S
• Chlorine Gas → Cl₂
• Fluorine Gas → F₂
• Bromine Molecule → Br₂
• Iodine Molecule → I₂
• Nitric Acid Anhydride → N₂O₅
• Sulphuric Acid Anhydride → SO₃

8. Miscellaneous

• Urea → CO(NH₂)₂
• TNT (Trinitrotoluene) → C₇H₅N₃O₆
• DDT → C₁₄H₉Cl₅
• Aspirin → C₉H₈O₄
• Ethanol → C₂H₅OH
• Glycerol → C₃H₅(OH)₃
• Formaldehyde → HCHO
• Chloroform → CHCl₃