Modern Physics MCQs
1. What is the chemical symbol for the element gold? A) Au B) Ag C) Go D) Gl Answer: A) Au 2. Which of the following is NOT a noble gas? A) Helium B) Neon C) Argon D) Hydrogen Answer: D) Hydrogen 3. What is the chemical formula for water? A) H2O2 B) CO2 C) H2O D) O2 Answer: C) H2O 4. Which subatomic particle has a negative charge? A) Proton B) Neutron C) Electron D) Nucleus Answer: C) Electron 5. What type of bond is formed when electrons are shared between atoms? A) Ionic bond B) Covalent bond C) Metallic bond D) Hydrogen bond Answer: B) Covalent bond 6. What is the atomic number of carbon? A) 6 B) 8 C) 12 D) 14 Answer: A) 6 7. Which gas is produced during photosynthesis? A) Oxygen B) Carbon dioxide C) Nitrogen D) Hydrogen Answer: A) Oxygen 8. What is the pH value of pure water? A) 7 B) 0 C) 14 D) 1 Answer: A) 7 9. Which element is essential for human respiration? A) Carbon B) Oxygen C) Nitrogen D) Hydrogen Answer: B) Oxygen 10. What is the chemical formula for methane? A) CH4 B) CO2 C) H2O D) NH3 Answer: A) CH4 11. Which gas is commonly known as laughing gas? A) Nitrous oxide B) Carbon monoxide C) Sulfur dioxide D) Ammonia Answer: A) Nitrous oxide 12. What is the main component of natural gas? A) Methane B) Ethane C) Propane D) Butane Answer: A) Methane 13. Which chemical element has the symbol “Fe”? A) Iron B) Gold C) Silver D) Lead Answer: A) Iron 14. What is the chemical formula for sodium chloride? A) NaCl B) NaOH C) Na2CO3 D) NaNO3 Answer: A) NaCl 15. What is the chemical symbol for potassium? A) K B) P C) Ka D) Po Answer: A) K 16. Which gas is produced when vinegar and baking soda are mixed? A) Carbon dioxide B) Oxygen C) Hydrogen D) Nitrogen Answer: A) Carbon dioxide 17. What is the molecular formula for glucose? A) C6H12O6 B) H2O C) CO2 D) CH4 Answer: A) C6H12O6 18. Which element has the atomic number 1? A) Hydrogen B) Helium C) Lithium D) Boron Answer: A) Hydrogen 19. What is the chemical formula for sulfuric acid? A) HCl B) H2SO4 C) HNO3 D) H2O2 Answer: B) H2SO4 20. Which metal is liquid at room temperature? A) Mercury B) Lead C) Iron D) Zinc Answer: A) Mercury 21. What is the chemical formula for ammonia? A) NH3 B) N2 C) NH4 D) NO2 Answer: A) NH3 22. What is the process of conversion of a solid directly into vapor called? A) Melting B) Evaporation C) Sublimation D) Condensation Answer: C) Sublimation 23. Which metal is an essential component of hemoglobin? A) Iron B) Copper C) Zinc D) Magnesium Answer: A) Iron 24. What is the chemical symbol for silver? A) Si B) Ag C) Au D) Sr Answer: B) Ag 25. What is the lightest element in the periodic table? A) Hydrogen B) Helium C) Lithium D) Oxygen Answer: A) Hydrogen 26. Which of the following is a greenhouse gas? A) Nitrogen B) Oxygen C) Carbon dioxide D) Argon Answer: C) Carbon dioxide 27. What is the chemical formula for hydrogen peroxide? A) H2O B) H2O2 C) HO2 D) H3O Answer: B) H2O2 28. What is the chemical symbol for lead? A) Ld B) Pb C) Pl D) Pd Answer: B) Pb 29. Which of the following is NOT a noble gas? A) Helium B) Neon C) Xenon D) Nitrogen Answer: D) Nitrogen 30. What is the chemical formula for table salt? A) NaCl B) KCl C) HCl D) NaOH Answer: A) NaCl 31. Which element has the chemical symbol “He”? A) Helium B) Hydrogen C) Hafnium D) Holmium Answer: A) Helium 32. What is the chemical formula for methane? A) CH3 B) CH4 C) CO2 D) H2O Answer: B) CH4 33. Which gas is essential for photosynthesis? A) Oxygen B) Carbon dioxide C) Nitrogen D) Hydrogen Answer: B) Carbon dioxide 34. What is the chemical formula for water? A) H2O B) HCl C) NaCl D) CO2 Answer: A) H2O 35. Which element has the symbol “Fe”? A) Iron B) Gold C) Silver D) Lead Answer: A) Iron 36. What is the atomic number of carbon? A) 6 B) 8 C) 12 D) 14 Answer: A) 6 37. Which gas has the chemical formula “CO2”? A) Carbon monoxide B) Carbon dioxide C) Nitrogen dioxide D) Sulfur dioxide Answer: B) Carbon dioxide 38. What is the pH value of pure water? A) 7 B) 0 C) 14 D) 1 Answer: A) 7 39. Which gas is produced during cellular respiration? A) Oxygen B) Carbon dioxide C) Nitrogen D) Hydrogen Answer: B) Carbon dioxide 40. What is the chemical formula for methane? A) CH4 B) CO2 C) H2O D) NH3 Answer: A) CH4 41. Which gas is commonly used in balloons to make them float? A) Hydrogen B) Oxygen C) Nitrogen D) Carbon dioxide Answer: A) Hydrogen 42. What is the chemical formula for sodium chloride? A) NaCl B) NaOH C) Na2CO3 D) NaNO3 Answer: A) NaCl 43. What is the chemical symbol for potassium? A) K B) P C) Ka D) Po Answer: A) K 44. Which gas is produced when vinegar and baking soda are mixed? A) Carbon dioxide B) Oxygen C) Hydrogen D) Nitrogen Answer: A) Carbon dioxide 45. What is the molecular formula for glucose? A) C6H12O6 B) H2O C) CO2 D) CH4 Answer: A) C6H12O6 46. Which element has the atomic number 1? A) Hydrogen B) Helium C) Lithium D) Boron Answer: A) Hydrogen 47. What is the chemical formula for sulfuric acid? A) HCl B) H2SO4 C) HNO3 D) H2O2 Answer: B) H2SO4 48. Which metal is liquid at room temperature? A) Mercury B) Lead C) Iron D) Zinc Answer: A) Mercury 49. What is the chemical formula for ammonia? A) NH3 B) N2 C) NH4 D) NO2 Answer: A) NH3 50. What is the process of conversion of a solid directly into vapor called? A) Melting B) Evaporation C) Sublimation D) Condensation Answer: C) Sublimation