Why do less reactive metals form less stable compounds?

Less reactive metals form less stable compounds because they have a lower tendency to donate or accept electrons.

In more detail, the reactivity of a metal is determined by its ability to lose electrons and form positive ions. This process is known as oxidation. The more readily a metal can lose its electrons, the more reactive it is. This is because metals react by losing electrons to non-metals, forming a positive ion and a compound in the process.

Less reactive metals, such as gold or platinum, have a lower tendency to lose their electrons. This is due to the fact that these metals have more protons in their nucleus, which results in a stronger attraction for the electrons. This stronger attraction makes it more difficult for the electrons to be lost, hence these metals are less reactive.

When less reactive metals do form compounds, these compounds are less stable. This is because the bonds in these compounds are not as strong, due to the lower reactivity of the metal. The metal ions in these compounds are not as strongly attracted to the non-metal ions, resulting in a weaker bond and a less stable compound.

For example, gold, a less reactive metal, forms compounds such as gold chloride (AuCl3) which are less stable and can be easily broken down. On the other hand, sodium, a highly reactive metal, forms compounds like sodium chloride (NaCl) which are very stable and difficult to break down.

In summary, the reactivity of a metal, determined by its ability to lose electrons, directly affects the stability of the compounds it forms. Less reactive metals form less stable compounds due to their lower tendency to donate or accept electrons.