Question

1. justify why the number of valence electrons stays the same within a group using electron configurations.

i need a hint
groups or families have similar properties and a play a key role in determining these properties. once an atom has a b, additional electrons are placed in a higher energy level.

Explanation:

Valence electrons are the electrons in the outermost shell of an atom. In a group (vertical column) of the periodic table, atoms have the same number of valence electrons. This is because as we move down a group, the additional electrons are added to inner shells (lower - energy levels) while the outermost shell (valence shell) has the same number of electrons. For example, in Group 1 (alkali metals), lithium (\(Li\)) has an electron configuration of \(1s^{2}2s^{1}\), sodium (\(Na\)) has \(1s^{2}2s^{2}2p^{6}3s^{1}\), and potassium (\(K\)) has \(1s^{2}2s^{2}2p^{6}3s^{2}3p^{6}4s^{1}\). The outermost shell (\(n = 2\) for \(Li\), \(n=3\) for \(Na\), \(n = 4\) for \(K\)) has 1 electron in each case.

Answer:

A. valence electrons; B. full valence shell