Is Potassium a Metal or Nonmetal? (+ 3 Facts to Know)

Potassium is a metal. It is a soft, silvery-white metal that belongs to the alkali metal group in the periodic table. ¹ Like other metals, potassium has the ability to conduct electricity, has a metallic luster, and is malleable and ductile. ²

Well, this was just a simple answer. But there are few more things to know about this topic which will make your concept super clear.

So let’s dive right into it.

Explanation: Why is potassium a metal?

Potassium is a metal because it has the physical and chemical properties of metals.

• Appearance: Potassium is a solid at room temperature and has a shiny metallic appearance. This is because it has a crystalline structure, which allows its atoms to pack closely together, forming a continuous lattice that reflects light. ^{3 4 5}
• Conductivity: Potassium is a good conductor of heat and electricity. This is due to its structure, which allows electrons to move freely through the lattice of atoms, making it a good conductor of both heat and electricity. ^{6 7}
• Malleability and ductility: Potassium is malleable and ductile, meaning it can be easily bent or shaped without breaking. This is because its atoms are held together by metallic bonds, which allow them to slide past each other without breaking the bonds. ⁸
• Ionization energy: Potassium has a low ionization energy and readily loses its outermost electron to form a positively charged ion. This is a characteristic property of metals, as they tend to lose electrons to form cations. ⁹
• Chemical behavior: Potassium reacts with water to produce hydrogen gas and an alkaline solution, which is also a typical behavior of metals. ¹⁰

Therefore, based on its physical and chemical properties, potassium is classified as a metal.

What type of metal is potassium classified on the periodic table?

Potassium is classified as an alkali metal on the periodic table. 

This is because it belongs to group 1, which is also known as the alkali metals group. 

The alkali metals are a group of highly reactive metals that have one valence electron and readily lose it to form a +1 cation. ¹¹

In addition to potassium, other alkali metals include lithium, sodium, rubidium, cesium, and francium. 

These metals share similar properties due to their electronic configuration and their position in the periodic table.

Does potassium exist as a pure metal?

Potassium does exist as a pure metal, but it is not commonly found in its elemental form in nature due to its high reactivity. Instead, it is usually found in combination with other elements in minerals such as sylvite (KCl) and carnallite (KMgCl₃ · 6H₂O). ^{12 13}

To obtain pure potassium metal, it can be isolated through the process of electrolysis, where a potassium-containing compound, such as potassium chloride, is dissolved in a solvent and an electric current is passed through it. ¹⁴

This causes the potassium ions to be reduced at the cathode, forming pure potassium metal.

However, pure potassium metal is highly reactive and must be stored under oil or in an inert atmosphere to prevent it from reacting with air or moisture. ¹⁵

It can even react violently with water, releasing hydrogen gas and generating enough heat to ignite the hydrogen. 

Therefore, due to its high reactivity and safety concerns, pure potassium metal is not commonly used or found in everyday applications.

Further reading

Is Calcium a Metal or Nonmetal?
Is Titanium a Metal or Nonmetal?
Is Chromium a Metal or Nonmetal?
Is Iron a Metal or Nonmetal?
Is Cobalt a Metal or Nonmetal? 

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