Reactive Metal with Bases
Metallic elements such as sodium, potassium, calcium, and magnesium are known to react with bases. Among these, sodium and potassium are highly reactive metals that can vigorously react with bases.

Reaction with Bases
When a reactive metal like sodium or potassium comes into contact with a base such as sodium hydroxide (NaOH) or potassium hydroxide (KOH), a chemical reaction occurs. The metal displaces hydrogen from the hydroxide ion, forming metal hydroxide and hydrogen gas as products.
The general equation for this reaction is:
2M(s) + 2OH^-(aq) -> 2MOH(aq) + H2(g)
Here, M represents the metal, and MOH is the metal hydroxide formed. The hydrogen gas produced during this reaction can often be observed as bubbles.

Observing the Reaction
When a reactive metal is added to a base, the reaction is exothermic, releasing heat energy. This can be observed by an increase in temperature of the reaction mixture. Additionally, the formation of metal hydroxide can often be seen as a precipitate forming in the solution.

Applications
The reaction of reactive metals with bases is utilized in various industrial processes. For example, the production of sodium hydroxide (caustic soda) involves the reaction of sodium metal with water. Similarly, the reaction of potassium metal with hydroxide solutions is used in the production of potassium hydroxide.
In conclusion, reactive metals such as sodium and potassium can react with bases to form metal hydroxides and hydrogen gas. This reaction is exothermic and can be observed by changes in temperature and the formation of a precipitate. The reaction has important industrial applications in the production of various chemicals.