In the following table, six elements A, B, C, D, E and F (here letters are not the usual symbols of the elements) of the modern Periodic Table with atomic numbers 3 to 18 are given:


(a) Which of these is (i) a noble gas, (ii) a halogen?


(b) If B combines with F, what would be the formula of the compound formed?


(c) Write the electronic configurations of C and E.

(a) (i) G with atomic number 10 is a noble gas because it has complete octet.

(ii) F with atomic number 17 is a halogen.


(b) B with atomic number 11 has 1 valence electron and F with atomic number 17 has 7 valence electrons so the formula of the compound formed would be BF.


(c) Electronic configuration of C and E are


E8- 2, 6


C12- 2, 8, 2


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