Which metal is placed at the top of the reactivity series?

Correct option is D

Correct Answer: D Potassium

Explanation:
The reactivity series is a list of metals arranged in order of their decreasing reactivity. Potassium is placed at the top of the reactivity series because it is highly reactive. This high reactivity is due to its ability to lose its outermost electron easily to form a positive ion (K⁺). Potassium reacts vigorously with water, oxygen, and acids, releasing hydrogen gas and producing strong exothermic reactions.

Key properties of Potassium in the reactivity series:

• It is an alkali metal and belongs to Group 1 of the periodic table.
• It reacts violently with water, forming potassium hydroxide (KOH) and hydrogen gas.
• It has low ionization energy, making it highly reactive.

Reactivity Series Order (Top to Bottom):
Potassium > Sodium > Calcium > Magnesium > Aluminium > Zinc > Iron > Lead > Copper > Silver > Gold.

Information Booster:

•  Metals at the top of the reactivity series are most reactive and easily lose electrons.
•  Potassium reacts so strongly that it must be stored under oil to prevent reactions with moisture and air.
•  Elements lower in the series, such as copper, silver, and gold, are less reactive and often found in their native states in nature.
•  The reactivity of a metal determines its ability to displace another metal in a compound.
•  Potassium's reactivity also limits its industrial applications due to safety concerns.

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