Question

Justify the position of hydrogen in the periodic table?

Answer 1

Hydrogen resembles alkali metals in the following aspects.

1. Electronic configuration 1s¹ as alkali metals have ns¹.
2. Hydrogen forms unipositive H⁺ ion like alkali metals Na⁺, K⁺.
3. Hydrogen forms halides (HX), oxides (H₂O) peroxide (H₂O₂) like alkali metals (NaX. Na₂O, Na₂O₂).
4. Hydrogen also acts as a reducing agent like alkali metals. Hydrogen resembles halogens in the following aspects.
5. Hydrogen has a tendency to gain one electron to form a hydride ion (H^–) as halogens to form a halide ion. (X^–).
6. Comparing the properties of hydrogen with alkali metals and with halogens, we can conclude that hydrogen resembles more alkali metals. In most of the compounds, hydrogen exists in a +1 oxidation state.
7. Therefore, it is reasonable to place the hydrogen in group 1 along with alkali metals as shown in the latest periodic table published by IUPAC.