The elements of a period of the periodic table are given below in order, from left to right, with one of its elements missing
`{:(Li, Be, B, C, 0, F, N e):}`
i] To which period does these elements belong?
ii] One element of this period is missing. Which is the missing element and where should it be placed?
iii] Which one of these elements in the period shows property of catenation?
iv] Which one of the above belongs to the halogen series?
v] Identify the noble gas.

Explanation

i] These elements belong to the 2nd period.
ii] The missing element is nitrogen (N). It should be placed between carbon (C) and oxygen (O).
III] Carbon (C) shows the property of catenation.
iv] Fluorine (F) belongs to the halogeri serius.
 v] Neon (Ne) is the noble gas.