Here's why:
* Electron Configuration: Alkali metals have only one valence electron (electron in the outermost shell). This single electron is easily lost, making them highly reactive.
* Electropositivity: They are highly electropositive, meaning they readily lose their valence electron to form positive ions.
* Ionization Energy: They have low ionization energies, meaning it takes relatively little energy to remove the valence electron.
Examples of Alkali Metals:
* Lithium (Li)
* Sodium (Na)
* Potassium (K)
* Rubidium (Rb)
* Cesium (Cs)
* Francium (Fr)
Remember, reactivity increases as you move down the alkali metal group. This is because the valence electron is further from the nucleus and easier to remove.
