question_answer 61)

  The electronic configurations of three elements X, Y and Z are X ? 2, 8; Y ? 2, 8, 7 and Z ? 2, 8, 2. Which of the following is correct? (a) X is a metal                                                                   (b) Y is a metal (c) Z is a non-metal                                                          (d) Visa non-metal and Z is a metal

Answer:

                  (d) Y is a non-metal because it requires one electron to complete its octate. Z is a metal because it looses two electrons to complete its octate. X is an inert gas as it has complete octate.