How do alkali metals react with acids?

Alkali metals react with acids to produce a salt and hydrogen gas.

Alkali metals, found in Group 1 of the Periodic Table, are known for their highly reactive nature. This is due to the single electron in their outermost shell which they are eager to lose in order to achieve a stable electron configuration. When an alkali metal comes into contact with an acid, a chemical reaction occurs, resulting in the formation of a salt and the release of hydrogen gas.

For instance, if you were to react sodium (an alkali metal) with hydrochloric acid, the reaction would be as follows: 2Na + 2HCl -> 2NaCl + H2. Here, sodium chloride (a salt) and hydrogen gas are produced. This is a type of single displacement reaction, where the sodium displaces the hydrogen in the hydrochloric acid, forming sodium chloride and releasing hydrogen gas.

The reaction is exothermic, meaning it releases heat. This can be observed as the reaction often causes the hydrogen gas to ignite, creating a small flame. The reactivity of the alkali metals increases as you move down the group in the Periodic Table. This means that potassium, for example, would react more violently with an acid than sodium.

It's important to handle these reactions with care in a lab setting. Due to the production of hydrogen gas and the exothermic nature of the reaction, there is a risk of explosion if the reaction is not carefully controlled. Always remember to wear appropriate safety gear and follow your teacher's instructions when conducting these experiments.