Question

comparing reactivity of different metals
rank the metals from most reactive (1) to least reactive (3).
tantalum:
niobium:
dubnium:

Explanation:

These metals are in Group 5 of the periodic table. For transition metals in the same group, reactivity generally increases as you go down the group due to increased atomic size and weaker attraction between valence electrons and the nucleus. Dubnium is below Niobium and Tantalum, Niobium is above Tantalum.

Answer:

Tantalum: 2
Niobium: 3
Dubnium: 1