Question

Hydrogen is not a metal then why it is put in the reactivity series of metals ?

Answer 1

hydrogen is very reactive element and it forms compounds with most of the elements known to us that's why it is included the reactivity series of metals

Answer 2

Answer:

Hydrogen, being a non-metal is in the reactivity series of metals because it has the ability of lose electron to form positive ion.

Explanation:

In chemical terms, we define metals as those elements who form positive ions by losing electrons(elements form positive ion if they lose electrons as the net charge of the  protons and the electrons will the positive and vice versa) and non-metals form negative ions by gaining electrons. Hydrogen is the exception in this case as it loses electron to form positive hydrogen ion. As hydrogen shows the chemical property of metals. It is included in the reactivity series of metals.