The number of valence electrons found in an atom of a Group A element is equal to
A)eight.
B)its mass number.
C)its atomic number.
D)eight minus the group number.
E)its group number.

Question

Quizplus · Accepted Answer

The number of valence electrons for elements in the main groups (Group A elements) of the periodic table is equal to their group number. For example, Group 1 elements have 1 valence electron, Group 2 elements have 2, and so on up to Group 18, which have 8 valence electrons (except for Helium, which has 2).

The Number of Valence Electrons Found in an Atom of a Group