Question

1. The group to which the element with electronic confiiguration of 2, 8, 2 belongs?

2. The element placed below hydrogen in group 1

3. The element which forms a diatomic molecule

Answer 1

Hello Sinorarai,

Here’s the answer to your questions.

1) Since the valence electrons in the electronic configuration of the metal are 2, which is less than 4, therefore the valency is equal to 2.Hence it belongs to group 2 i.e. alkaline earth metal group.

2) The elements whose electronic configuration contains 1 electron in the valence shell are categories as group 1 elements. Since alkali metal has 1 electron in their outermost shell, they are called group 1 elements. Lithium metal is the first alkali metal in the group 1 which is placed after hydrogen. (Remember hydrogen is not an alkali metal, but it has electronic configuration similar to alkali metals i.e. 1 electron in the valence shell.)

3) There are many elements which form diatomic molecules. For e.g. Nitrogen (N_2), Oxygen (O₂₎, etc.

Hope this answer solves your query.

Best Wishes!