Alkali metals are a group of elements found in Group 1 of the periodic table. These metals are very reactive, which means they easily combine with other substances.

One reason they are so reactive is because of their electronic setup. Each alkali metal has just one extra electron. This makes them really eager to lose that electron. When they do, they can become stable, just like the noble gases.

Why Are They So Reactive?

1. Low Ionization Energy: As you go down the group, it becomes easier for these metals to lose their outer electron. This is because their energy levels change, and they don’t hold on to that electron as tightly.

2. Making Strong Bases: When alkali metals mix with water, they create strong bases and hydrogen gas. For example, if sodium (Na) reacts with water, this happens:

   • Sodium + Water → Sodium Hydroxide + Hydrogen Gas
   • This is written as: $2 \text{Na} + 2 \text{H}_2\text{O} \rightarrow 2 \text{NaOH} + \text{H}_2$

3. High Electronegativity Difference: Alkali metals also easily form compounds with other elements. This is because they really want to lose that one electron, which makes them more reactive.

In short, alkali metals are super eager to react because of their structure and how they behave with other elements!