Why can hydrogen be placed in either group 1 or 7 on the periodic table?

Answer 1

Hydrogen can be in both group 1 and group 7 due to it's valence shell. Hydrogen only needs 2 (or 0) electrons to be stable.

Because it has 1 electron, it can either accept one (like a group 7 element) or give one away (like a group 1 element).

It can act like either group.

Answer 2

Hydrogen can be placed in group number 1 or (but not normally) in group number 17 because it has some properties similar to both groups.

• On one hand , it exhibits the property of alkali metalsby losing one electron to get a positive charge ( H --> H+ + e-).
• On the other hand, it exhibits one of the properties of halogens such as fluorine as it (though rather seldom) can adopt one electron to form the hydride anion ( H + e- --> H - ), much like fluoride F -.

  But this is not a strong argument for placing Hydrogen in group 17, so I would stick to: Hydrogen in group one.

Answer 3

The short answer is that like group I elements, it has 1 electron in the outer shell, and can donate this to become H^+ (proton). Like group VII elements, it needs only 1 electron to be stable (like the noble gas helium), and will gain an electron to form the hydride ion (H^-). There are many other similarities between hydrogen and group I metals and between hydrogen and group VII halogens to justify placing it in either group.

Answer 4

Hydrogen can be placed in either group 1 or 7 on the Periodic Table because it shares some properties with alkali metals in group 1 (e.g. forming H+ ions) and some properties with halogens in group 7 (e.g. forming H- ions). However, it is typically placed separately in its own group due to its unique characteristics.

Answer 5

Hydrogen is placed in group 1 of the periodic table of Mendeleev because some similarities with alkali metals exist.

Answer 6

Why hydrogen can be in group 1 and also can be in group 7