The atomic numbers of three elements `A,B` and `C` are given below:
Element Atomic number
`{:("Element","Atomic number"),(A,5),(B,7),(C,10):}`
(i) Which element belongs to group 18? (ii) Which element belongs to group 15?
(iii) Which element belongs to group 13? (iv) To which period/ periods do these elements belong?

Answer

(i) C (ii) B (iii) A (iv) 2nd period

Explanation

NA