MCQ Detailed View

Non-metals are generally gases (like oxygen, nitrogen, chlorine) or solids (like sulfur, iodine, phosphorus) at room temperature. However, there is one unique exception: bromine (Br₂), which is the only non-metal that exists as a liquid at room temperature and pressure.

Bromine is a reddish-brown, volatile liquid with a strong unpleasant odor. It is located in Group 17 (Halogens) of the periodic table, along with fluorine, chlorine, iodine, and astatine. Its atomic number is 35.

The melting and boiling points of bromine explain why it exists as a liquid at room conditions:

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  Melting point: –7.2 °C

  
  


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  Boiling point: 58.8 °C

  
  

Since its melting point is below room temperature and its boiling point is above room temperature, bromine remains a liquid under normal conditions (~25 °C). Other halogens, such as chlorine and fluorine, are gases because their boiling points are much lower than room temperature, while iodine is a solid because its melting point is above room temperature.

Key properties of bromine:

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  Appearance: Reddish-brown liquid

  
  


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  State: Only non-metal liquid at room temperature

  
  


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  Volatile: Easily evaporates, forming red-brown vapors

  
  


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  Solubility: Slightly soluble in water, more soluble in organic solvents

  
  


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  Toxic: Bromine and its vapors are poisonous and corrosive

  
  

Uses of bromine:

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  In production of flame retardants

  
  


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  In water purification (as a disinfectant)

  
  


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  In manufacturing of brominated organic compounds

  
  


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  Historically used in photography (silver bromide in films)

  
  

Thus, bromine stands out as the only non-metal in liquid state under ordinary conditions, making it an important example of how physical properties vary within the same group in the periodic table.