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

Chlorine is a gas at room temperature and normal atmospheric pressure. ¹ However, chlorine can be compressed to a liquid and solidified under specific conditions of low temperature and high pressure. 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.

Why does chlorine exist as a gas at room temperature?

Chlorine (Cl₂) exists as a gas at room temperature because its boiling point is -34.04°C (-29.27°F) and its melting point is -101.5°C (-150.7°F). This means that at room temperature (typically around 20-25°C or 68-77°F), chlorine is well above its boiling point and therefore exists as a gas. ³

Chlorine is a halogen element and has a relatively low atomic mass and small size, which means that the intermolecular forces of attraction between its molecules are weak. This weak intermolecular force allows the chlorine molecules to move around freely as a gas at room temperature and atmospheric pressure.

It’s important to note that chlorine gas is toxic and can be harmful to human health in high concentrations. Therefore, it is important to handle it with care and follow proper safety procedures.

Does chlorine exist in liquid or solid state?

Yes, chlorine can exist in both liquid and solid states under certain conditions.

At normal atmospheric pressure, chlorine gas can be condensed into a liquid state at a temperature of -34.04°C (-29.27°F) or below. This is the boiling point of chlorine, and if the gas is cooled below this temperature, it will condense into a liquid state. Liquid chlorine is a clear amber-colored liquid that has a density of 1.56 g/cm³ at its boiling point.

If liquid chlorine is further cooled, it can solidify into a yellow-green crystalline solid. The melting point of chlorine is -101.5°C (-150.7°F), which means that the solidification of liquid chlorine occurs at temperatures below this point. ⁴

It’s important to note that both liquid and solid chlorine are highly reactive and potentially dangerous substances. ⁵ They should be handled with extreme caution, and appropriate safety measures and protective equipment should be used to prevent exposure to chlorine gas or liquid. ^{6 7}

How is gaseous chlorine different from solid chlorine and liquid chlorine?

Gaseous chlorine, solid chlorine, and liquid chlorine are different states of the same element, chlorine (Cl2), and they exhibit different physical and chemical properties.

• Physical State: Gaseous chlorine exists as a yellow-green gas at room temperature and atmospheric pressure, while solid chlorine is a yellow-green crystalline solid, and liquid chlorine is a clear amber-colored liquid. ^{8 9}
• Molecular Interactions: In the gaseous state, chlorine molecules are relatively far apart and exhibit weak intermolecular forces of attraction. In contrast, solid and liquid chlorine molecules are much closer together, and they exhibit stronger intermolecular forces of attraction.
• Density: Gaseous chlorine has the lowest density of the three states, followed by liquid chlorine, and then solid chlorine. This is because the molecules are more tightly packed in the solid and liquid states, resulting in a higher density.
• Reactivity: The reactivity of chlorine is dependent on its physical state. Gaseous chlorine is highly reactive and can readily combine with other elements or compounds, which can result in the production of corrosive or toxic compounds. Liquid and solid chlorine are also reactive but to a lesser extent than gaseous chlorine. ¹⁰

In summary, gaseous, liquid, and solid chlorine differ in their physical and chemical properties, including their molecular interactions, density, and reactivity. It’s essential to handle all forms of chlorine with extreme care and take appropriate safety measures to avoid exposure to its toxic and potentially harmful effects.

Further reading

Is Sulfur a Solid, Liquid or Gas?
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? 

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