Ionic compounds are generally brittle and break into pieces when pressure is applied due to the arrangement of ions in a regular lattice structure.

Not all metals react with oxygen, water, and acids. Therefore, using these reactions alone may not provide sufficient evidence to establish a complete order of reactivity among all metals.

By observing displacement reactions, we can directly see which metals can displace others from their compounds. This allows us to establish a more accurate order of reactivity among metals.

Displacement reactions are simple and straightforward: if one metal displaces another from its solution, it indicates that the displacing metal is more reactive. This simplicity makes displacement reactions an effective method for determining the relative reactivity of metals.

Studying displacement reactions allows us to establish a more accurate order of reactivity among metals by directly observing which metals can displace others from their compounds.