Question

12. An element has electronic configuration. 2, 8, 7
(i) What type of ion will it form? (ii) Name the unit to measure its atomic radius.
(iii) Give the electronic configuration of an element that lies above this element.
(iv) Give the electronic configuration of an element that belongs to 4th period but in 17th group.

Answer 1

Answer:

i) 2,8,7 so it will form -ve ion. it needs 1 electron to complete the octet. The element is chlorine and the ion is chloride i.e. Cl-

ii) Angstrom is the unit Å

iii) The element above chlorine in the periodic table is Fluorine F (2,7)

iv) element that that belongs to 4th period but in 17th group is Bromine Br (35) 2,8,18,7

Explanation:

concept of valency and periodic table applied.. good luck