Question

Is hydrogen placed above the alkali metals because it is a metal?

Answer 1

The chemical element hydrogen has the symbol H and the atomic number 1. The lightest element in the periodic table is hydrogen. Under normal circumstances, hydrogen is a gas composed of diatomic molecules with the formula ${{H}_{2}}$ . It's odourless, colourless, non-toxic, and extremely flammable. Hydrogen is the most abundant chemical element in the universe, accounting for around 75% of all ordinary stuff. The Sun, for example, is mostly made up of hydrogen in its plasma state. The majority of hydrogen on the planet is found in molecule forms like water and organic substances. Each atom of the most common hydrogen isotope has one proton, one electron, and no neutrons.

Complete answer:
Because hydrogen has an atomic number of one, it has only one electron in its atom and consequently only one electron in its outermost shell, making it the first element in the periodic table. The electrical configuration of elements determines their placement in the periodic table. This structure resembles alkali metals ( $n{{s}^{1}}$ ), which contain one electron in their outermost shell. By absorbing one electron, it may achieve the noble gas configuration of helium. This property is quite similar to that of the halogen family ( $n{{s}^{2}}\text{ }n{{p}^{5}}$ ), which is likewise missing one electron to complete the octet of electrons in its shell.
Hydrogen resembles alkali metals when it loses an electron and becomes a cation, but when it gets an electron and becomes a uni-negative ion, it resembles halogens. The location of hydrogen in the periodic table was a significant question based on these features.
Despite its similarity to halogens and alkali metals, hydrogen is substantially distinct from both. As a result, the location of hydrogen in the periodic table must be carefully considered. When hydrogen loses one electron, the size of its nucleus shrinks to about $1.5\text{ }\times {{10}^{-3}}pm$ , which is very tiny relative to the atomic sizes of typical metals, and therefore hydrogen ion does not exist freely in nature.
To sum up, Hydrogen is neither a metal nor a non-metal.
It is found in the periodic table's alkali metals column, although in its elemental state it is a gas; it is only there because of its single electron and atomic number of 1. Hydrogen prefers a +1 charge, but if a cation has a strong Lewis Acid, hydrogen can interact with it and end up with a -1 charge and a lone pair of electrons instead. EXAMPLE: NaH The location in the periodic table isn't always set, but it's in group 1 because of its primary ionic charge of +1.

Note:
Moving on to compound formation, hydrogen produces oxides, halides, and sulphides that are similar to alkali metals, but it has a far higher ionisation enthalpy than alkali metals, therefore it lacks metallic properties under normal conditions. In terms of ionisation enthalpy, hydrogen is determined to be more similar to halogens than alkali metals.