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cast, , Chapter, Practice, , Objective Questions, , 1. The first model of an atom was given by, , (NCERT Exemplar), a) Neils Bohr (b) E. Goldstein, (c) Rutherford (d) JJ Thomson, , 2. Rutherford's alpha («.) particles scattering, , experiment resulted into discovery of, (b) proton (NCERT Exemplar), , (d) atomic mass, , (a) electron, {c) nucleus in the atom, , 3. Match the following Columns., 1A Column B, , , , Column A, , , , , , ‘The distribution of electrons, into different orbit of an atom., , ‘The stability of atom could not, be explained by him., , A. [:J-Thomson (i), , B. E.Goldstein (i), , , , (iii) Discovered the presence of, new radiation called canal rays., , ‘oposed that electrons are, embedded in a positive sphere, , “C. Neils Bohr, , , , , , , , , , , , , , “D. E.Rutherford ” (iv), , , , , , , , , , , , , BCD, (a) (ii) @) (i) Gv), (c) (i) (ii) Gv) Gi), , i 4 © 10), , (b) (iv) Gii) @) Gi), , (d) (ii) (iv) (ii) @), , 4. Which of the following figure do not represent, Bohr’s model of an atom correctly? (NCERT Exemplar), , (i), , (ii) (ili) (iv), , (b) (ii) and (iii), (d) (i) and (iv), , (a) (i) and (ii), (c) (ii) and (iv), 5. Who discovered neutron?, (a) J. Chadwick, (c) Bohr, , (b) Dalton, (d) Rutherford, , aluminium atom, , 6. The electron distribution in an nium atom i, (a) 2, 8,3 (b) 2, 8,2 (c) 8,2,3 A235, 7. Which one of the following elements has 2 8, 5,2, electronic configuration?, (c) Silver ) Pallac, , (b) Copper, following is the valency of an element, onfiguration?, , (a) Calcium, 8. Which of the ;, ifit has 2, 8, 2 electronic ¢, (a)2 (b) 4 (c)6 d) 0, 9. Elements with valency 1 are (NCERT Exemplar, (a) always metals (b) always metalloids, (c) either metals or non-me!, 10. Which of the following represents a correct chemi, formula ? (NCERT Exemplar, (a) Ca (d) NaS, Tl. The formula of chloride of a metal M is MC\,, the, the formula of the phosphate of metal M will be, @M,PO, (b)MPO, —(c)M2(PO,)s_ (A) MPO., 12. The number of electrons in an element X is 15 and, the number of neutrons is 16. Which of the following, , is the correct representation of the element?, (NCERT Exemplar, , (@ RX, , tals (d) always non-metal, , (0) NaSO,, , (b) BiPO,, , , , (a) BX (b) 3X (©) 1gX, , 13. Identify the Mg* ion from the figure where, n and, , represent the number of neutrons and protons, (NGERT Exempla, , respectively., , , , oe, , 15., , , , 16