Question

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

Explanation:

Step1: Recall metal - reactivity series

In general, based on the metal - reactivity series and properties of these metals, darmstadtium (Darmstadtium is a synthetic element and very little is known about its chemistry, but as a heavy metal in the lower part of the periodic table it is likely to be less reactive) is less reactive. Nickel is moderately reactive. Titanium is more reactive than nickel in many common chemical environments due to its position in the periodic table and its tendency to form stable oxides.

Step2: Rank the metals

Titanium is the most reactive among them, so it gets rank 1. Nickel is moderately reactive, so it gets rank 2. Darmstadtium is the least reactive, so it gets rank 3.

Answer:

Titanium: 1
Nickel: 2
Darmstadtium: 3