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Glite Dictionary
potassium alum

potassium alum

6.5
A white crystal people use to clean water, help dye cloth, and make skin less oily
  • noun
  • /pəˈtæsiəm ˈæləm/
  • Specialized
translation icon : alumbre de potasio
  • In traditional water purification, potassium alum is added to help clarify the liquid.

Examples

  • Potassium alum is also used as an astringent in some aftershave products.

  • In the textile industry, potassium alum is used in dyeing processes to fix colors to fabrics.

  • The chemist measured out the potassium alum crystals for the experiment.

  • The chemical formula for potassium alum is KAl(SO4)2·12H2O.

  • Many industries use potassium alum for water purification.

  • Potassium alum is commonly used in water purification to help remove impurities from drinking water.

  • As a natural astringent, potassium alum is effective in reducing skin irritation after shaving.

Synonyms

potash alum
vspotassium alum
  • Specialized
8.3

A white crystal used to dye cloth, purify water, and treat skin

is the more formal name for the same compound

Surface Forms

potassium alum singular
potassium alums plural

Morphology

potassium + alum

The compound is a straightforward chemical name formed by combining the constituent meanings: 'potassium' specifies the cation and 'alum' names the type of double-sulfate salt. This compositional, non-idiomatic naming follows transparent morphological and scientific naming patterns, so a B1 learner who knows both words can infer the MWE's meaning.

Etymology

Potassium alum comes from old words: alum was the name for a bitter salt used to clean cloth and water, and potassium refers to 'potash', a salt made from plant ashes. So the name suggests a white cleansing salt, which fits why we still use potassium alum today to clarify water, fix dyes, and as an astringent.