Question

How many valence electrons do group 2 have?

Answer 1

The number of valence electrons can easily be calculated if one knows the electronic configuration and filling of orbitals in each group of the periodic table.

Complete step by step answer:
The group 2 elements are called alkaline earth metals. Beryllium, Magnesium, Calcium, Barium, Strontium and Radium are the members of group 2. These are less metallic in nature and are less electropositive in nature when compared to the group1 elements or alkali metals.
We know that the modern periodic table arranges the element on the basis of their respective atomic numbers and thus the whole periodic table is divided into several groups and periods. Starting from the left is the first group and at the very right is the eighteenth group which is the noble gas group. In each group, there is a specific number of electrons in the valence shell which is uniform throughout the entire group.
Valence shell or valence orbital is the orbital which is present at the outermost region in the atoms. These valence shells have some electrons called valence electrons and these electrons are responsible for the reaction process taking place. Whenever an electron is withdrawn or added to this valence shell, its main aim is to complete the octet of the element.
Now, if we know the electronic configuration of the elements in group 2, we can easily find the number of valence electrons in their outermost shell. The second group of the periodic table is the group concerned with the filling of the s orbital. Thus, the element in the second group of the periodic table will have an outermost s orbital filled with two electrons of different spins.

Hence, the number of valence electrons in group 2 is two.

Note: The elements in group 2 will always try to eliminate or donate both of its electrons in the outermost shell to complete its octet and to achieve the nearest noble gas configuration and that’s why the oxidation state of group 2 elements is commonly + 2.