Elements in the same group have
A)the same atomic number.
B)the same number of neutrons.
C)the same number of electrons.
D)the same number of valence electrons.

Question

Quizplus · Accepted Answer

Elements in the same group have the same number of valence electrons (electrons in the outermost energy level). Valence electrons are responsible for the chemical properties and reactivity of an element, which is why elements in the same group have similar chemical properties. The number of protons (atomic number) and neutrons can vary within a group, while the number of electrons may vary between different energy levels of an atom in the same group.

Elements in the Same Group Have