This quiz works best with JavaScript enabled. Home > Class 9 > Class 9 Science Chapter 3 Atoms And Molecules – Quiz 5 🏠 Homepage 📘 Download PDF Books 📕 Premium PDF Books Class 9 Science Chapter 3 Atoms And Molecules Quiz 5 (25 MCQs) Quiz Instructions Select an option to see the correct answer instantly. 1. The smallest part of an element is known as the A) Periodic Table. B) Atom. C) Group. D) Period. Show Answer Correct Answer: B) Atom. 2. Which element has the chemical symbol 'Fe'? A) Fluorine. B) Iron. C) Francium. D) Fermium. Show Answer Correct Answer: B) Iron. 3. State the atomicity of $s_8$ A) Diatomic. B) Monoatomic. C) Polyatomic. D) Tetraatomic. Show Answer Correct Answer: C) Polyatomic. 4. Electrons are not factored into atomic mass because: A) They are so small their mass is negligible. B) They're not in the nucleus. C) They're too big. D) They move so quickly their mass is zero. Show Answer Correct Answer: A) They are so small their mass is negligible. 5. The formula of Ammonium Sulphate is ..... A) NH$_{4}$SO$_{4}$. B) NH$_{4}$SO$_{2}$. C) (NH$_{4}$)$_{2}$SO$_{4}$. D) NH$_{2}$SO$_{4}$. Show Answer Correct Answer: C) (NH$_{4}$)$_{2}$SO$_{4}$. 6. The relative molecular mass of Na2S2O3.5H2O is A) (a) 250 amu. B) (b) 250 g. C) C) 248 amu. D) (d) 248 g. Show Answer Correct Answer: D) (d) 248 g. 7. The molecular formula of potassium nitrate is ..... A) KNO. B) When. C) KNO$_{3}$. D) KNO$_{2}$. Show Answer Correct Answer: C) KNO$_{3}$. 8. The compounds or elements present at the end of a reaction A) Reactants. B) Catalyst. C) Products. D) Energy. Show Answer Correct Answer: C) Products. 9. Which law states that mass can neither be created nor be destroyed and given by ..... A) Law of conservation. B) Law of definite, Antonie Lavoisier. C) Law of conservation, Proust. D) None of the above. Show Answer Correct Answer: A) Law of conservation. 10. The no. of moles in 32 g of Helium are A) 2 mole. B) 4 mole. C) 8 mole. D) 18 mole. Show Answer Correct Answer: B) 4 mole. 11. The symbol of Potassium is A) Pa. B) K. C) Na. D) Pt. Show Answer Correct Answer: B) K. 12. What is a compound? A) Two different elements bonded together. B) Two of the same elements bonded together. C) A mixture of different substances. D) Two substances stuck together with glue. Show Answer Correct Answer: A) Two different elements bonded together. 13. The chemical symbol for nitrogen gas is A) In. B) N2. C) N. D) IN. Show Answer Correct Answer: B) N2. 14. The lightest element is A) Hydrogen. B) Helium. C) Carbon. D) Copper. Show Answer Correct Answer: A) Hydrogen. 15. Which of the following is a noble gas A) Helium. B) Oxygen. C) Aluminium. D) Hydrogen. Show Answer Correct Answer: A) Helium. 16. The atomic symbol of Iron is ..... A) Fe. B) I. C) And. D) Fu. Show Answer Correct Answer: A) Fe. 17. All atoms are most stable with (or would "prefer") how many electrons in their valence shell? A) 1. B) 2. C) 8. D) 18. Show Answer Correct Answer: C) 8. 18. Combination of atoms of same elements is known as A) Molecule. B) Element. C) Compound. D) Atom. Show Answer Correct Answer: A) Molecule. 19. Which of the following has maximum number of atoms? A) 1g of H$_{2}$O. B) 1g of O$_{2}$. C) 1g of CO$_{2}$. D) 1g of CH$_{4}$. Show Answer Correct Answer: D) 1g of CH$_{4}$. 20. What is the mass of 1 mol of Nitrogen atoms? A) 14g. B) 1.Hgg. C) 1410g. D) Hgum. Show Answer Correct Answer: A) 14g. 21. What is lacking in the meristematic tissue from the following? A) Dense cytoplasm. B) Nucleus. C) Cellulose. D) Vacuole. Show Answer Correct Answer: D) Vacuole. 22. Number of atoms of O in 34 gram H$_{2}$O$_{2}$ is(Given:O = 16 u, H = 1 u) A) N$_{A}$. B) 2 N$_{A}$. C) 3 N$_{A}$. D) 4 N$_{A}$. Show Answer Correct Answer: B) 2 N$_{A}$. 23. How many molecules are present in 2.00 moles of H$_{2}$O? A) 124 x 10$^{24 }$molecules of H$_{2}$O. B) 1.20 x 10$^{23 }$molecules of H$_{2}$O. C) 1.20 x 10$^{24}$ molecules H$_{2}$O. D) 124. Show Answer Correct Answer: C) 1.20 x 10$^{24}$ molecules H$_{2}$O. 24. Which postulate of Dalton's atomic theory can explain the law of definite proportions? A) Atoms combine in the ratio of small whole numbers to form compounds. B) The relative number and kinds of atoms are constant in a given compound. C) Atoms are indivisible particles, which cannot be created or destroyed in a chemical reaction. D) Atoms of different elements have different masses and chemical properties. Show Answer Correct Answer: B) The relative number and kinds of atoms are constant in a given compound. 25. How is matter recycled in ecosystems? A) Matter can take on different forms as it goes through different processes. B) Matter moves through ecosystems through biogeochemical cycles. C) Matter is recycled as organisms in different trophic levels consume and finally when decomposers return matter to the ecosystem. D) All of these are true. Show Answer Correct Answer: D) All of these are true. ← 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 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 10Class 9 Science Chapter 3 Atoms And Molecules Quiz 11 🏠 Back to Homepage 📘 Download PDF Books 📕 Premium PDF Books