Question

why are sodium and chlorine more active elements? ​

Answer 1

The primary difference between metals is the ease with which they undergo chemical reactions. The elements toward the bottom left corner of the periodic table are the metals that are the most active in the sense of being the most reactive. Lithium, sodium, and potassium all react with water, for example. The rate of this reaction increases as we go down this column, however, because these elements become more active as they become more metallic.

Answer 2

Explanation:

It takes more energy to remove an electron from a sodium atom to form an Na+ ion than we get back when this electron is added to a chlorine atom to form a Cl- ion. Once these ions are formed, however, the force of attraction between these ions liberates enough energy to make the following reaction exothermic.

Hence Sodium & Chlorine are more reactive

Hope it helps