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

Phosphorus is a nonmetal. Phosphorus is a reactive nonmetal and can easily combine with other elements to form compounds. It is an essential nutrient for life and is found in the bones, teeth, and DNA of all living things. ¹

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.

Why is phosphorus a nonmetal?

Phosphorus is a nonmetal for several reasons. 

1. Low melting and boiling point: Phosphorus has a relatively low melting and boiling point compared to most metals. At standard temperature and pressure, phosphorus is a white, waxy solid that melts at 44.1 °C and boils at 280.5 °C. Metals typically have much higher melting and boiling points due to the strength of the metallic bonds between their atoms. ²
2. Low density: Phosphorus has a low density compared to most metals. Its density is around 1.82 grams per cubic centimeter, which is similar to that of nonmetals like sulfur and selenium. ³ Metals, on the other hand, have higher densities due to their tightly packed atomic structures.
3. Higher electronegativity: Phosphorus has a tendency to gain electrons in chemical reactions, forming negatively charged ions or covalent compounds with other nonmetals. This is characteristic of nonmetals, which generally have a higher electronegativity and a stronger attraction for electrons than metals. ⁴
4. Lack of metallic properties: Phosphorus does not exhibit the typical metallic properties such as metallic luster, ductility, and conductivity. These properties arise from the delocalization of valence electrons in metallic bonding, which does not occur in nonmetals like phosphorus.

In summary, phosphorus is a nonmetal because of its relatively low melting and boiling points, low density, tendency to gain electrons, and lack of metallic properties.

Properties of phosphorus that classify it as a nonmetal

There are many properties of phosphorus that classify it as a nonmetal.

• Brittle: Phosphorus is brittle, meaning it is easily broken or shattered. This property is typical of nonmetals, which lack the ductility and malleability of metals.
• Poor thermal conductivity: Phosphorus is a poor conductor of heat, which is another property typical of nonmetals. In contrast, metals are good conductors of heat due to their free-flowing electrons. ⁵
• Insulator: Phosphorus is an insulator at room temperature and does not conduct electricity well. This is because it does not have any free electrons that can carry an electric charge. Metals, on the other hand, are typically good conductors of electricity due to their free electrons. ⁶
• Valence electrons: Phosphorus has five valence electrons, which is a typical number for nonmetals. ⁷ Valence electrons are the electrons in the outermost shell of an atom, and they play a crucial role in chemical bonding. Nonmetals tend to have higher electronegativities and attract electrons more strongly than metals, which is why they tend to gain electrons in chemical reactions.

In summary, phosphorus is a nonmetal because it is brittle, a poor conductor of heat and electricity, an insulator, and has a high electronegativity due to its valence electron configuration.

How is phosphorus different from other nonmetals?

Phosphorus is different from other nonmetals in several ways:

• Reactivity: Phosphorus is highly reactive, especially with oxygen, and can spontaneously ignite in air. This is due to its ability to form multiple oxidation states, which allows it to react with a wide range of elements and compounds. In contrast, other nonmetals such as nitrogen and carbon are relatively unreactive. ⁸
• Allotropy: Phosphorus exists in several allotropes or forms, including white, red, and black phosphorus. ⁹ Each allotrope has different physical and chemical properties, which makes phosphorus unique among nonmetals. For example, white phosphorus is highly reactive and flammable, while black phosphorus is a good conductor of electricity and has potential applications in electronics. ¹⁰
• Biological significance: Phosphorus is an essential element for life and is found in many biological molecules such as DNA, RNA, and ATP. ^{11 12} Other nonmetals such as carbon and nitrogen are also important for life, but they do not have the same widespread role as phosphorus.
• Commercial applications: Phosphorus has many commercial applications, such as in fertilizers, flame retardants, and semiconductors. ^{13 14} This makes it an important industrial element, while other nonmetals such as helium and neon do not have the same level of commercial significance.

In summary, phosphorus is different from other nonmetals due to its high reactivity, multiple allotropes, biological significance, and commercial applications. These properties make it a unique and important element among the nonmetals.

Further reading

Why is Sulfur a Nonmetal?
Is Chlorine a Metal or a Nonmetal?
Is Argon a Metal or Nonmetal?
Is Potassium a Metal or Nonmetal?
Is Calcium a Metal or Nonmetal? 

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