Use the metal reactivity series
Compare how easily each metal loses electrons
Observe reactions with water
Observe reactions with dilute acids
Observe displacement reactions from metal salt solutions
A more reactive metal displaces a less reactive metal from its compound
Faster and more vigorous reactions indicate higher reactivity
Less reactive metals show little or no reaction
Compare reaction products and rate of gas evolution
Use electrochemical series or standard electrode potentials
More negative electrode potential indicates higher reactivity