Alkali metals and alkaline earth metals are two groups of elements in the periodic table that share some similarities but also have some key differences.

Similarities

* Both alkali metals and alkaline earth metals are highly reactive.

* Both alkali metals and alkaline earth metals form ionic compounds with non-metals.

* Both alkali metals and alkaline earth metals have low ionization energies.

* Both alkali metals and alkaline earth metals are relatively soft and have low melting points.

Differences

* Alkali metals have one valence electron, while alkaline earth metals have two valence electrons.

* Alkali metals are more reactive than alkaline earth metals.

* Alkali metals form more basic oxides and hydroxides than alkaline earth metals.

* Alkali metals have lower melting points and boiling points than alkaline earth metals.

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

| Property | Alkali metals | Alkaline earth metals |

|---|---|---|

| Number of valence electrons | 1 | 2 |

| Reactivity | More reactive | Less reactive |

| Oxides and hydroxides | More basic | Less basic |

| Melting points and boiling points | Lower | Higher |