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Question
The elements of one short period of the periodic table are given below in order from left to right:
Li Be B C O F Ne
(a) To which period do these elements belong?
(b) One element of this period is missing. Which is the missing element and where should it be placed?
(c) Place the three elements, fluorine, beryllium and nitrogen, in the order of increasing electro negativity.
(d) Which one of the above elements belongs to the halogen series?
Solution
(a) Second period.
(b) Nitrogen. It should be placed between oxygen andcarbon.
(c) Beryllium < nitrogen < fluorine
(d) Fluorine (F)
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