100 Chemistry Quiz Questions & Answers 2026

Periodic Table Questions — 25 Questions

1. How many elements are in the periodic table? (118)
2. What does the atomic number represent? (Number of protons)
3. What is the chemical symbol for oxygen? (O)
4. What element has the symbol Fe? (Iron)
5. What is the most abundant element in the universe? (Hydrogen)
6. Which element is named after Marie Curie's home country? (Polonium — Po, after Poland)
7. What is the lightest metal? (Lithium)
8. What is the chemical symbol for mercury? (Hg — from Latin Hydrargyrum)
9. Which group of elements are the noble gases? (Group 18)
10. What element is essential for plant growth and is a component of chlorophyll? (Magnesium)
11. What is the chemical symbol for tungsten? (W — from German Wolfram)
12. How many elements are metals? (About 94 of 118 elements are metals)
13. What is the radioactive element used in nuclear power plants? (Uranium — U)
14. What is the element with the highest atomic number found naturally? (Uranium — atomic number 92)
15. What element is used in fluorescent light bulbs? (Mercury — though LEDs are replacing them)
16. What are halogens? (Group 17 elements — Fluorine, Chlorine, Bromine, Iodine, Astatine)
17. What is the chemical symbol for calcium? (Ca)
18. Which element glows in the dark? (Radium — but modern glow-in-the-dark uses phosphors)
19. What is the rarest naturally occurring element on Earth? (Astatine — less than 1 gram in Earth's crust)
20. What is the chemical symbol for nitrogen? (N)
21. Who created the periodic table? (Dmitri Mendeleev, 1869)
22. What is the element number 79? (Gold — Au)
23. Which element is liquid at room temperature (other than mercury)? (Bromine — Br)
24. What is the atomic number of carbon? (6)
25. What element is used in pencils? (Graphite — a form of Carbon)

Chemical Reactions & Compounds — 25 Questions

1. What is a chemical equation? (Representation of a chemical reaction using symbols and formulas)
2. What is a catalyst? (Substance that speeds up a reaction without being consumed)
3. What is combustion? (Rapid reaction with oxygen producing heat and light)
4. What is an acid? (Substance with pH below 7, donates protons in solution)
5. What is a base? (Substance with pH above 7, accepts protons in solution)
6. What is neutralization? (Reaction between an acid and a base to form salt and water)
7. What is the formula for sulfuric acid? (H₂SO₄)
8. What is photosynthesis chemically? (6CO₂ + 6H₂O + light → C₆H₁₂O₆ + 6O₂)
9. What is oxidation? (Loss of electrons — "OIL" in OIL RIG)
10. What is reduction? (Gain of electrons — "RIG" in OIL RIG)
11. What is a polymer? (Large molecule made of repeating smaller units called monomers)
12. What is the chemical name for baking soda? (Sodium bicarbonate — NaHCO₃)
13. What is the formula for hydrogen peroxide? (H₂O₂)
14. What is a precipitate? (Insoluble solid that forms from a solution during a reaction)
15. What is distillation? (Purification by heating and condensing vapors)
16. What is chromatography? (Technique for separating mixtures based on movement through a medium)
17. What happens in an endothermic reaction? (Heat is absorbed from the surroundings — feels cold)
18. What is the formula for ammonia? (NH₃)
19. What is electrolysis? (Using electrical current to drive a non-spontaneous chemical reaction)
20. What is a mole in chemistry? (6.022 × 10²³ particles — Avogadro's number)
21. What is the formula for ethanol? (C₂H₅OH)
22. What is a buffer solution? (Solution that resists changes in pH)
23. What is saponification? (Process of making soap — reaction of fat with strong base)
24. What is the universal indicator used for? (Measuring pH — changes color across the pH scale)
25. What is the Maillard reaction? (Chemical reaction between amino acids and sugars causing browning in cooked food)

Famous Chemists — 15 Questions

1. Who discovered radium and polonium? (Marie Curie — first woman to win a Nobel Prize)
2. Who invented dynamite? (Alfred Nobel, 1867)
3. Who discovered penicillin? (Alexander Fleming, 1928)
4. Who created the first periodic table? (Dmitri Mendeleev, 1869)
5. Who is known as the father of modern chemistry? (Antoine Lavoisier)
6. Who proposed the atomic theory in the early 19th century? (John Dalton)
7. Who discovered the electron? (J.J. Thomson, 1897)
8. Who proposed the nuclear model of the atom? (Ernest Rutherford, 1911)
9. Who developed the Bohr model of the atom? (Niels Bohr, 1913)
10. Who is Fritz Haber known for? (Haber-Bosch process — synthesizing ammonia for fertilizer)
11. Who discovered oxygen independently? (Carl Wilhelm Scheele and Joseph Priestley)
12. Who named oxygen and hydrogen? (Antoine Lavoisier)
13. Which scientist developed polymer chemistry? (Hermann Staudinger)
14. Who won two Nobel Prizes in different sciences? (Marie Curie — Physics 1903, Chemistry 1911)
15. Who discovered nylon? (Wallace Carothers at DuPont, 1935)