1. Reactivity of the Metals: Magnesium is a highly reactive metal, while gold is a relatively noble metal. Magnesium has a lower ionization energy and a more electropositive nature compared to gold. This means that magnesium atoms are more likely to lose their valence electrons and form positive ions, making them more reactive.
2. Electron Configuration: The electron configuration of magnesium and gold plays a role in their reactivity. Magnesium has a relatively loosely bound 3s² valence electron, which can be easily removed to form a cation (Mg²⁺). In contrast, gold has a completely filled 5d¹⁰6s¹ electron configuration, making its valence electrons more tightly bound and less available for chemical reactions.
3. Surface Properties: The surface properties of magnesium and gold also contribute to their reactivity differences. Magnesium has a more reactive surface that is prone to oxidation and reaction with atmospheric gases like CO2. Gold, on the other hand, has a more inert surface that resists oxidation and is less reactive towards CO2.
4. Formation of Compounds: When magnesium reacts with CO2, it forms magnesium carbonate (MgCO3), a stable compound. This reaction is driven by the release of energy in the form of heat. Gold, on the other hand, does not react with CO2 under normal conditions because it does not form a stable compound with it.
In summary, the high reactivity of magnesium, its loosely bound valence electrons, reactive surface, and the stability of magnesium carbonate contribute to its ability to react with CO2, while the noble nature, tightly bound valence electrons, inert surface, and lack of a stable compound formation prevent gold from reacting with CO2 under normal conditions.
