Metals that are more reactive than hydrogen in the reactivity series will react with acids to produce hydrogen gas. These metals include:

* Group 1 (Alkali Metals): Lithium (Li), Sodium (Na), Potassium (K), Rubidium (Rb), Cesium (Cs), Francium (Fr)

* Group 2 (Alkaline Earth Metals): Beryllium (Be), Magnesium (Mg), Calcium (Ca), Strontium (Sr), Barium (Ba), Radium (Ra)

* Aluminum (Al)

* Zinc (Zn)

* Iron (Fe)

* Tin (Sn)

* Lead (Pb)

Example Reaction:

Zinc + Hydrochloric Acid → Zinc Chloride + Hydrogen

Zn(s) + 2HCl(aq) → ZnCl₂(aq) + H₂(g)

Important Note:

* Noble metals (gold, silver, platinum) do not react with acids.

* The reaction of metals with acids can be affected by the concentration of the acid and the temperature.

* The hydrogen gas produced is flammable and should be handled with care.