Is Sulfur a Solid, Liquid or Gas? (+ 3 Things to Know)

Sulfur is a solid at room temperature and normal atmospheric pressure. Its melting point is 115.21°C (239.38°F) and its boiling point is 444.67°C (832.01°F), which means that it is well above its boiling point and therefore exists as a solid at room temperature. 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 does sulfur exist as a solid at room temperature?

Sulfur exists as a solid at room temperature because of its unique atomic structure and intermolecular forces. 

At room temperature, sulfur consists of eight-membered rings of S8 molecules held together by weak intermolecular forces known as van der Waals forces. ² These forces are not strong enough to break the bonds between the sulfur atoms and cause it to become a liquid or gas.

The S8 molecules in solid sulfur are arranged in a crystalline structure, where each molecule is surrounded by other molecules held together by van der Waals forces. This structure gives sulfur its characteristic brittle and crystalline appearance. ³

At higher temperatures, the thermal energy can overcome the intermolecular forces holding the S8 molecules together, causing sulfur to melt into a liquid and eventually vaporize into a gas. The melting point of sulfur is relatively low, at around 115 °C, and its boiling point is around 444 °C.

In summary, sulfur exists as a solid at room temperature because of the weak intermolecular forces between its S8 molecules, which are not strong enough to overcome the covalent bonds holding the sulfur atoms together and cause it to become a liquid or gas.

Does sulfur exist in a liquid state?

Yes, sulfur can exist in a liquid state under certain conditions.

Sulfur has a melting point of 115.21°C (239.38°F) and a boiling point of 444.6°C (832.3°F) at standard pressure (1 atm). At room temperature and pressure, sulfur is a solid, but if it is heated above its melting point, it will melt and become a liquid. ⁴

Sulfur can also exist in a liquid state under high pressure, even at temperatures below its melting point.

Furthermore, molten sulfur is commonly used in industrial processes, such as the production of sulfuric acid, fertilizers, and other chemicals. The liquid sulfur is stored and transported in insulated tanks, and it solidifies at room temperature. ⁵

How is solid sulfur different from liquid sulfur?

Solid sulfur and liquid sulfur have several differences in their physical and chemical properties.

Physical Properties:

• Solid sulfur is a brittle, yellow solid at room temperature, while liquid sulfur is a reddish-brown liquid. ^{6 7}
• Solid sulfur has a crystalline structure, while liquid sulfur has a non-crystalline or amorphous structure.
• Solid sulfur is not very conductive of electricity, while liquid sulfur is a good conductor of electricity. ⁸
• The density of liquid sulfur is greater than the density of solid sulfur.
• The viscosity of liquid sulfur is higher than that of solid sulfur.

Chemical Properties:

• The reactivity of sulfur increases with temperature, so liquid sulfur is more reactive than solid sulfur. ⁹
• Solid sulfur is relatively inert and stable, while liquid sulfur is more reactive and can undergo chemical reactions with other substances.
• Solid sulfur does not dissolve in water, while liquid sulfur is partially soluble in water and other polar solvents.
• Solid sulfur is not flammable, while liquid sulfur can ignite and burn in the presence of an ignition source. ¹⁰

Overall, the physical and chemical properties of solid sulfur and liquid sulfur are quite different, with liquid sulfur being more reactive and having different physical properties, such as higher density and viscosity. These differences make solid and liquid sulfur useful for different applications in various industries.

Further reading

Is Carbon Solid, Liquid or Gas?
Is Boron a Solid, Liquid or Gas?
Is Hydrogen a Solid, Liquid or Gas?
Is Mercury Solid, Liquid or Gas?
Is Phosphorus a Solid, Liquid or Gas? 

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