Question

Arrange Na, Ca, K, Mg in the descending order of their reactivity.

Answer 1

The reactivity series depicts the most reactive element at the top and the least reactive element at the bottom. The element that is more reactive has a higher tendency to lose electrons in order to form positive ions.

The elements are arranged in the descending order of their reactivity:

1. Potassium $\left(\mathrm{K}\right)$
2. Sodium $\left(\mathrm{Na}\right)$
3. Calcium $\left(\mathrm{Ca}\right)$
4. Magnesium $\left(\mathrm{Mg}\right)$

This arrangement is done by making use of the reactivity series. Potassium $\left(\mathrm{K}\right)$ and Sodium $\left(\mathrm{Na}\right)$ have a tendency to react quite vigorously with Water $\left({\mathrm{H}}_2\mathrm{O}\right)$. This is followed by Calcium $\left(\mathrm{Ca}\right)$ whereas Magnesium $\left(\mathrm{Mg}\right)$ barely reacts with cold Water $\left({\mathrm{H}}_2\mathrm{O}\right)$.