Answer:
Potassium
Explanation:
Most reactive metal in the reactivity series
The element in the question is referred to the alkali metal which is known as Potassium
Potassium is a highly reactive metal and reacts with Hydrochloric acid to
form a salt known as Potassium chloride and hydrogen gas.
Hcl + K ⇒ Kcl₍s₎ + H₂₍g₎
Potassium has a white color but when it reacts with water it explodes and
gives out a purple-red color as a result of the high excitation of electrons.
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