An element x has an atomic number of 20.which group and period does it belong to in the periodic table?

1 Answer
May 2, 2018

#"Group 2" and "Period 2"#

Explanation:

The the element #x# that has an atomic number of #20# is #"Calcium"#

Calcium has the electronic configuration as;

#1s^2 2s^2 2p^6 3s^2 3p^6 4s^color(blue)2 or [Ar] 4s^color(blue)2#

The group it belongs to is #"Group 2"#

Since it has #2# electrons in the outter most shell..

Shell configuration as #"K, L, M, N"#;

#2, 8, 8, 4#

The period it belongs to is #"Period 4"#

Since it occupies four shells..