molal

IPA/ˈməʊ.ləl/
IPA/ˈmoʊ.ləl/

molal — adjective

  • molalpositive
  • more molalcomparative
  • most molalsuperlative

1. describing a solution in which the concentration is expressed as moles of dissol

1.形容詞C1
釋義

describing a solution in which the concentration is expressed as moles of dissolved substance per unit mass of solvent

例句

The lab technician prepared a 0.5-molal potassium chloride solution because its concentration is unchanged by cooling.

attributive use: [number]-molal solution of [substance]

Professor Amara explained that molal concentration stays the same even when the temperature changes.

collocation: molal concentration

同義詞
  • molality-based

    less common, descriptive compound used when emphasizing the measurement system

反義詞
  • molar

    refers to concentration per liter of solution rather than per kilogram of solvent

文法句型

[number]-molal solution of [substance]

molal [noun]

用法筆記

Frequently used attributively before nouns such as 'solution' or 'concentration'. Unlike 'molar', molal values do not change with temperature because they are based on mass rather than volume.

常見錯誤

❌We prepared a 1-molal solution by adding one mole of salt to one liter of water.
✅We prepared a 1-molal solution by adding one mole of salt to one kilogram of water.
💡Molal concentration uses mass of solvent (kilograms), not volume (liters).
❌The molal concentration changed when we heated the solution.
✅The molal concentration stayed the same when we heated the solution.
💡Molality is based on mass, which does not change with temperature, unlike molarity.