Common chemical formula quiz 20 common chemical formula. Test yourself. Show All Answers Hide All Answers 1. Water H2O 2. Carbon dioxide CO2 3. Table salt or sodium chloride NaCl 4. Hydrogen gas H2 5. Nitrogen gas N2 6. Oxygen gas O2 7. Ozone O3 8. Sodium hydroxide NaOH 9. Methane CH4 10. Sulfuric acid H2SO4 11. Hydrochloric acid HCl 12. Nitric acid HNO3 13. Copper sulfate CuSO4 14. Calcium carbonate CaCO3 15. Ammonia NH3 16. Acetic acid CH3COOH 17. Glucose C6H12O6 18. Ethanol CH3CH2OH 19. Butane C4H10 20. Baking soda or sodium hydrogen carbonate NaHCO3 Permission is granted to use for educational purposes with acknowledgment of source © chemicalformula.org