Is Hydrogen an Alkali Metal? Why?

Hydrogen is not an alkali metal, but it is placed in the same group in the periodic table because it has one electron in its outer shell. ¹ Alkali metals are highly reactive metals, while hydrogen is a gas. ^{2 3}

Well, this was just a simple answer. But there are few more things to know about this topic which will make your concept super clear.

So let’s dive right into it.

Why is hydrogen not an alkali metal?

Hydrogen is not an alkali metal because most of its physical and chemical properties are not similar to that of the alkali metals. 

Alkali metals are soft, silvery-white metals that are highly reactive. They have low ionization energies and form ionic compounds with nonmetals. ^{4 5 6}

Hydrogen, on the other hand, is a gas at room temperature and pressure. ⁷ It is less reactive than the alkali metals and does not form ionic compounds. 

Hydrogen is also a nonmetal, while the alkali metals are metals.

In the periodic table, hydrogen is placed in the same column as the alkali metals because it has the same outer electron configuration (1s¹). ⁸

However, hydrogen has many other properties that are different from the alkali metals. 

For example, hydrogen has a much higher ionization energy than the alkali metals. ⁹

This means that it is more difficult to remove an electron from hydrogen than it is from an alkali metal.

Hydrogen also has a much lower melting point and boiling point than the alkali metals. ^{10 11 12}

Overall, hydrogen is not an alkali metal because it does not have the same physical and chemical properties as the other alkali metals. 

Hydrogen is a gas, while the alkali metals are metals. Hydrogen is also less reactive than the alkali metals and does not form ionic compounds.

Differences between hydrogen and alkali metals

Here are some of the key differences between hydrogen and the alkali metals:

• Physical state: Hydrogen is a gas at room temperature, while the alkali metals are solids or liquids.
• Ionization energy: Hydrogen has a higher ionization energy than the alkali metals, meaning that it is more difficult to remove an electron from a hydrogen atom. ¹³
• Reactivity: Hydrogen is less reactive than the alkali metals. ¹⁴ This is because hydrogen has a higher ionization energy, which makes it more difficult for hydrogen to lose an electron and form ions.
• Type of compounds formed: Hydrogen forms covalent compounds with nonmetals, while the alkali metals form ionic compounds with nonmetals. ¹⁵

Here is a table summarizing the key differences between hydrogen and the alkali metals:

Property	Hydrogen	Alkali metals
Physical state at room temperature	Gas	Solid
Ionization energy	Higher	Lower
Reactivity	Less reactive	More reactive
Type of compounds formed with nonmetals	Covalent	Ionic

Therefore, while hydrogen has some similarities to the alkali metals, it does not have all of the same properties. As a result, it is not considered to be an alkali metal.

Why is hydrogen placed in group 1 (along with metals)?

Hydrogen is placed in group 1 (along with metals) because it has similar chemical properties to the alkali metals. 

Hydrogen has one electron in its valence shell, like the alkali metals. ¹⁶ It can also lose this electron to form a positive ion, like the alkali metals. Hydrogen also forms compounds with other elements in a similar way to the alkali metals.

However, hydrogen is not a metal. It is a gas at room temperature, while metals are solids. Hydrogen also has a higher ionization energy than the alkali metals, which means that it is more difficult to remove an electron from hydrogen. ^{17 18}

Despite these differences, hydrogen is still placed in group 1 because of its similar chemical properties to the alkali metals.

Further reading

What Group is Hydrogen in?
Why is Hydrogen in Group 1?
Is Hydrogen Reactive?
Why is Hydrogen Diatomic?
Is Hydrogen a Compound? 

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