An atom has electronic configuration 2, 8, 2.
(i) What is the atomic number of this element ?
(ii) What is its valency ?
(iii) To which of the following elements would it be chemically similar and why ? (Be-4, 0-8. Justify your answer.)

Explanation

(i) 12.
(ii) 2.
(iii) Be.
Because Be has two electrons in its valence shell. Given element also has two electrons in its valence shell.
Since valence electrons determine the chemical property, hence the given element has same chemical properties as that of Be.