What is meant by the metal reactivity series? State its importance (any two points)

Explanation: The metal reactivity series is a list in which metals are grouped in decreasing order of their chemical reactivity.

Its importance are:

•  From potassium to gold, the ease with which a metal in solution loses an electron(s) and forms a positive ion decreases.
•  Hydrogen is included in the activity series because, like metals, it loses an electron in most chemical reactions and becomes positively charged (H+).
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Final answer: The metal reactivity series is a list in which metals are grouped in decreasing order of their chemical reactivity.