Why is hydrogen placed at the top of the periodic table and not in group 1?

Answer 1

Hydrogen is in fact in group 1 physically although not considered an alkali metal. It is at the top because the table is arranged by increasing atomic number; hydrogen is atomic number one, so it's first on the table.

Answer 2

Hydrogen is placed at the top of the Periodic Table because it has unique properties that differ from both alkali metals in Group 1 and halogens in Group 17. It can either behave like a metal or a nonmetal depending on the conditions, so it is placed separately to reflect its distinct characteristics.

Answer 3

Because hydrogen contains 17 more atomic properties than the noble gases, therefore, it relates closet to lithium than to the noble gases

Answer 4

The elements are placed in order by number of protons. Hydrogen has 1 proton so it comes first.

Answer 5

Because a hydrogen atom has one valence electron, as do the other elements in group 1A.