Class IX Chapter : Structure of Atom Date of Taking Test : September 8, 2025 Time: 20 Minutes 1. 2, 8, 8 is the electronic configuration of which of the following species? (a) Argon (b) Calcium (c) Ca2+ and Ar (d) Potassium None 2. Dalton’s atomic theory successfully explained (a) (i), (ii) and (iii) (b) (i), (iii) and (iv) (c) (ii), (iii) and (iv) (d) (i), (ii) and (iv) None 3. Which of the following is the electronic configuration of aluminium Al +3? (a) 2, 8, 3 (b) 2, 8 (c) 2, 8, 6 (d) 2, 8, 8, 3 None 4. Which of the following statements about Rutherford’s model of atom are correct? (a) (i) and (iii) (b) (ii) and (iii) (c) (i) and (iv) (d) Only (i) None 5. Which of the following is true for an element? (a) (i) and (ii) (b) (i) and (iii) (c) (ii) and (iii) (d) (ii) and (iv) None 6. In Thomson’s model of the atom, which of the following statements is correct? (a) (i), (ii) and (iii) (b) (i) and (iii) (c) (i) and (iv) (d) (i), (iii) and (iv) None 7. Identify the Mg2+ ion from the given figures, where n and p represent the number of neutrons and protons respectively. (a) Option (a) (b) Option (b) (c) Option (c) (d) Option (d) None 8. Which of the following statements is correct about the atoms of elements given below: (a) These are isotopes with the same number of neutrons (b) These are isotopes with the same number of protons (c) These are isobars with same mass number (d) These are isobars with the same number of neutrons. None 9. If an element has 5 electrons, and 6 neutrons, identify the correct statement about this. (a) The element has atomic number 5, valency +3, and mass number 11 (b) The element has atomic number 6, valency +3, and mass number 11 (c) The element has atomic number 6, valency +5, and mass number 5 (d) The element has atomic number 5, valency +5, and mass number 11 None 10. Identify the incorrect statement (a) the outermost shell of an atom is known as the valence shell. (b) The number of electrons present in the valence shell or outermost shell is known as valence electrons. (c) the combining capacity of an element is known as its valency. (d) The valency of the element is zero if it has 9 electrons in its valence shell. None 11. Assertion (A): Rutherford selected a gold foil for his scattering experiment. Reason (R): Gold foil could be converted into a thin layer of about 1000 atoms thick. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true and R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true None 12. Assertion (A): The discovery of two fundamental particles (electrons and protons) inside the atom, led to the failure of Dalton’s atomic theory. Reason (R): According to Dalton’s atomic theory, the atom is the smallest indivisible and indestructible. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true and R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true None 13. Assertion (A): Protium, deuterium, and tritium are the isotopes of hydrogen. Reason (R): All these three contain one electron, one proton and one neutron. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true and R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true None 14. Assertion A): Neutrons are present in the nucleus of all the atoms. Reason (R): Except for hydrogen (protium), all the atoms have neutrons. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true and R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true None 15. Assertion (A): Isobars occupy the same position in the Modern periodic table. Reason (R): Isobars have different numbers of electrons, protons, and neutrons but have the same mass number. (a) Both A and R are true and R is the correct explanation of A (b) Both A and R are true and R is NOT the correct explanation of A (c) A is true but R is false (d) A is false but R is true None 1 out of 1 Leave a Reply Cancel replyYour email address will not be published. Required fields are marked *Name * Email * Website Comment * Save my name, email, and website in this browser for the next time I comment.