Definition

1. Noun:
   • A measure of concentration in chemistry: Molar concentration is the amount of a substance (solute), measured in moles, present in one liter of solution. It is a standard unit for expressing the concentration of a chemical species in a solution.

Usage

• Molar concentration is a fundamental concept in chemistry used to perform quantitative calculations involving solutions, such as in dilution, reaction stoichiometry, and equilibrium.
• It is typically denoted by the symbol M (e.g., a 0.5 M solution) or by square brackets around the chemical formula (e.g., [NaCl]).
• The formula for calculating molar concentration is: Molarity (M) = moles of solute / liters of solution.

Examples

• Noun:
  • The experiment requires a sodium chloride solution with a molar concentration of 0.1 M.
  • To calculate the mass needed, you must first know the desired molar concentration and the volume of the solution.
  • Increasing the molar concentration of the acid will speed up the reaction.

Advanced Usage

• "Standard solution": A solution whose precise molar concentration is known, used in titrations.
  • The chemist prepared a standard solution of potassium permanganate with a molar concentration of 0.02 M for the titration.

Variants and Related Words

• Molarity (n): A synonym for molar concentration. The terms are often used interchangeably.
  • The molarity of the solution was too high for the sensitive assay.
• Molality (n): A different concentration unit defined as moles of solute per kilogram of solvent, not per liter of solution.
• Concentration (n): The general term for the amount of a substance per defined space. Molar concentration is a specific type of concentration.

Synonyms

• Molarity: The most direct synonym.
• Molar: Used adjectivally (e.g., molar solution).

Related Phrases

• "Molar concentration of...": The standard phrasing to specify the solute.
  • We need to determine the molar concentration of hydroxide ions in the sample.

Noun

1. concentration measured by the number of moles of solute per liter of solution