This quiz works best with JavaScript enabled. Home > Class 9 > Class 9 Science Chapter 3 Atoms And Molecules – Quiz 16 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 9 Science Chapter 3 Atoms And Molecules Quiz 16 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. Atomic mass can be best defined as: A) 1/16th the mass of an oxygen atom. B) 1/13th the mass of a carbon atom. C) 1/12th the mass of a carbon atom. D) 1/15th the mass of an oxygen atom. Show Answer Correct Answer: C) 1/12th the mass of a carbon atom. 2. An Indian sage who postulated the atom in his VISHESIKA SUTRA was ..... A) Maharishi's sympathy. B) Maharishi Kashapa. C) Maharishi's sympathy idea d Kashapa, that shark. D) None of the above. Show Answer Correct Answer: C) Maharishi's sympathy idea d Kashapa, that shark. 3. When elements combine they form A) Elements. B) Atoms. C) Compounds. D) Salt. Show Answer Correct Answer: C) Compounds. 4. ..... combine together to form molecules. A) Atoms. B) Compounds. C) Mixtures. D) Pikmon. Show Answer Correct Answer: A) Atoms. 5. Which one of these items is not a solid with a repeating pattern?Calculate the relative molecular mass of H2S. A) 16 a.m.u. B) 64 a.m.u. C) 18 a.m.u. D) 34 a.m.u. Show Answer Correct Answer: D) 34 a.m.u. 6. The central region of an atom where its neutrons and protons are is called it's ..... A) Nucleus. B) Electron cloud. C) Core. D) Center. Show Answer Correct Answer: A) Nucleus. 7. The Latin name of Potassium is ..... A) Sodium. B) Potassium. C) Plum bum. D) None of the above. Show Answer Correct Answer: B) Potassium. 8. The positive particles of an atom are called ..... A) Electrons. B) Atoms. C) Neutrons. D) Protons. Show Answer Correct Answer: D) Protons. 9. Thickening of suberin chemical on the wall of sclerenchyma cells makes them impermeable to air and water. A) True. B) False. C) All the above. D) None of the above. Show Answer Correct Answer: B) False. 10. Valency of Hydrogen is ..... A) 1. B) 2. C) 3. D) 4. Show Answer Correct Answer: A) 1. 11. The mass of one atom of oxygen is A) $\frac{\left(16\right)}{\left(6.022\times10^{23}\right)}g$. B) $\frac{\left(32\right)}{\left(6.022\times10^{23}\right)}g$. C) 16g. D) 8g. Show Answer Correct Answer: A) $\frac{\left(16\right)}{\left(6.022\times10^{23}\right)}g$. 12. What is the molar mass of CO$_{2}$$_{}$? A) 22.0 g/mol. B) 28.0 g/mol. C) 44.0 g/mol. D) 56.0 g/mol. Show Answer Correct Answer: C) 44.0 g/mol. 13. In ammonia NH$_{3, Nitrogen and Hydrogen are in the ratio ..... by mass.}$ A) 14:5. B) 14:3. C) 14:8. D) 14:2. Show Answer Correct Answer: B) 14:3. 14. A change in the physical state can be brought about A) Only when energy is given to the system. B) Only when energy is taken out from the system. C) When energy is either given to or taken out from the system. D) Without any energy change. Show Answer Correct Answer: C) When energy is either given to or taken out from the system. 15. In a compound such as water, the ratio of the mass of hydrogen to the mass of oxygen is always ..... , whatever the source of water. A) 14:6. B) 1:9. C) 1:8. D) 8:1. Show Answer Correct Answer: C) 1:8. 16. How many times heavier is one atom of carbon than the atom of oxygen A) 1.25. B) 1.5. C) 1.33. D) 1.23. Show Answer Correct Answer: C) 1.33. 17. If an element gains one or more electrons, it became A) Positively charged. B) Negatively charged. C) Neutral. D) None of the above. Show Answer Correct Answer: B) Negatively charged. 18. What happens to electrons during ionic bonding? A) They are transferred from one atom to another. B) They are shared between the 2 atoms. C) Each atom loses an electron. D) Each atom takes only one electron each. Show Answer Correct Answer: A) They are transferred from one atom to another. 19. The idea of divisibility of matter was given by A) On slayama. B) Antoine Lavoisier. C) Democritus. D) Maharishi kanad. Show Answer Correct Answer: D) Maharishi kanad. 20. Mass can neither be created nor destroyed. it is a ..... A) Mass recreation. B) Mass is cannot reform. C) Law of conservation of mass. D) Law of conservation. Show Answer Correct Answer: C) Law of conservation of mass. 21. The number of electrons present in the 'L' shell of O is A) 3. B) 4. C) 5. D) 6. Show Answer Correct Answer: D) 6. 22. Atomic number of hydrogen is A) 5. B) 7. C) 3. D) 1. Show Answer Correct Answer: D) 1. 23. What is the atomic number? A) The number of protons. B) The number of protons and neutrons. C) The number of neutrons. D) The number of protons and electrons. Show Answer Correct Answer: A) The number of protons. 24. All matter is composed of A) Energy. B) Atoms. C) Electrons. D) Compounds. Show Answer Correct Answer: B) Atoms. 25. Molecules can be termed as? (Generally) *Choose the most appropriate option- A) Cluster of Elements. B) Cluster of Compounds. C) Cluster of Mixtures. D) Cluster of Atoms. Show Answer Correct Answer: D) Cluster of Atoms. ← PreviousNext →Related QuizzesClass 9 Science Chapter 3 Atoms And Molecules Quiz 1Class 9 Science Chapter 3 Atoms And Molecules Quiz 2Class 9 Science Chapter 3 Atoms And Molecules Quiz 3Class 9 Science Chapter 3 Atoms And Molecules Quiz 4Class 9 Science Chapter 3 Atoms And Molecules Quiz 5Class 9 Science Chapter 3 Atoms And Molecules Quiz 6Class 9 Science Chapter 3 Atoms And Molecules Quiz 7Class 9 Science Chapter 3 Atoms And Molecules Quiz 8Class 9 Science Chapter 3 Atoms And Molecules Quiz 9Class 9 Science Chapter 3 Atoms And Molecules Quiz 10 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books