Final answer:
The least reactive metal is likely among the noble metals like gold and platinum, due to their position at the bottom of the activity series and resistance to oxidation. Alkali metals, on the other hand, are highly reactive while noble metals demonstrate stability and low reactivity due to their unique electronic structures.
Step-by-step explanation:
Inert metals are the metals that have the least reactivity. These metals are found at the bottom of the activity series, which means they have the least tendency to be oxidized. The most inert metal and least reactive is likely to be found among the noble metals such as gold and platinum, which do not corrode or oxidize easily under normal circumstances.
When referring to metallic and nonmetallic character, we assess the reactivity of metals based on their tendency to lose electrons during chemical reactions, which is typically low for inert metals. In contrast, alkali metals like cesium and francium are among the most reactive due to their tendency to lose their single valence electron easily. However, due to their high reactivity and rarity, we rarely encounter francium in nature and cesium reacts explosively with water.
In comparison, metals like silver can be exposed to water without reacting, making it a candidate for the title of the least reactive metal. This characteristic allows for its use in applications such as drinking vessels and jewelry, which would not be possible with more reactive metals. While reactivity tends to increase with increasing atomic number within the metal groups, inert metals like gold and platinum deviate from this trend due to their unique electronic configurations and the relative stability of their electron shells.