Answer
Please see the work below.
Work Step by Step
The valence shell electrons are represented as dots in Lewis symbols.
The group number of representative elements represents the dots in the Lewis symbol.
(a) Be and (c) Ca are in group 2A. Hence there are two electrons in their valence shell.
(b) K is in group 1A. Hence there is one electron in its valence shell.
(d) Ga is in group 3A. Hence there are three electrons in its valence shell.
(e) O is in group 6A. Hence there are six electrons in its valence shell.
(f ) Br, (h) I, and ( j) F are in group 7A. Hence there are seven electrons in their valence shell.
(g) N and (i) As are in group 5A. Hence there are five electrons in their valence shell.
