10th Class Science Solved Paper - Science-2015 Outside Delhi Set-III

  • question_answer
    Given below are some elements of the modern periodic table. Atomic number of the element is given in the parentheses:
                A(4), B(9), C(14), D(19), E(20)
    (a) Select the element that has one electron in the outermost shell. Also write the electronic configuration of this element.
    (b) Which two elements amongst belong to the same group? Give reason for your answer.
    (c) Which two elements amongst these belong to the same period? Which one of the two has bigger atomic radius?


                A = 2, 2
                B = 2, 7
                C = 2, 8, 4
                D = 2, 8, 8, 1
                E = 2, 8, 8, 2
    (a) D = 2, 8, 8, 1
    (b) A and E, as they have same number of valence electrons.
    (c) A and B, D and E as their number of shells are same, A is bigger than B and D is bigger than E.


You need to login to perform this action.
You will be redirected in 3 sec spinner