You're asking about the least reactive metals, which are found at the bottom of the reactivity series. Here's a breakdown:

Least Reactive to Most Reactive:

1. Gold (Au)

2. Platinum (Pt)

3. Silver (Ag)

4. Mercury (Hg)

5. Copper (Cu)

6. Iron (Fe)

7. Zinc (Zn)

8. Aluminum (Al)

9. Magnesium (Mg)

10. Calcium (Ca)

11. Sodium (Na)

12. Potassium (K)

13. Lithium (Li)

Why are some metals less reactive?

* Electron Configuration: Metals with tightly held outer electrons are less likely to lose them and participate in chemical reactions. Gold, for instance, has a very stable electron configuration.

* Ionization Energy: The energy required to remove an electron from an atom. Metals with high ionization energies tend to be less reactive.

Important Notes:

* This list is a general guideline. The reactivity of metals can be influenced by factors like temperature, the presence of other substances, and the form of the metal (solid, liquid, etc.).

* While gold and platinum are known for their low reactivity, they can still react under certain conditions.

Let me know if you'd like to know more about specific metals or how reactivity is determined!