Question

As we move down the alkali metals group, from lithium to sodium to potassium, the elements become progressively:

Answer 1

As we move down the alkali metals group, from lithium to sodium to potassium, the elements become progressively reactive.

The reactivity of Group 1 elements increases as you go down the group because the atoms get larger as you go down the group. The attraction between the nucleus and outer electron gets weaker as you go down the group - so the electron is more easily lost.