When a crude solid is made of mainly one substance and has some impurities, it is purified, this process is called ________

The correct answer is Crystallization.

Key Points

• Crystallization is a chemical purification technique used to separate a pure solid substance from its impurities.
• It involves the formation of solid crystals from a solution or a melt, ensuring that the main substance crystallizes while impurities remain in the solution.
• This method is commonly used to purify organic compounds, salts, and metals in industries and laboratories.
• Factors such as temperature, concentration, and solvent choice play a critical role in determining the efficiency of crystallization.
• Crystallization is widely regarded as a cost-effective and efficient method for obtaining high-purity substances.

Additional Information

• Filtration
  • Filtration is a physical separation process used to remove insoluble impurities from liquids or gases.
  • Unlike crystallization, it does not purify the dissolved components of a solution.
  • Commonly used in water treatment, laboratory experiments, and industrial processes.
• Purification
  • Purification refers to any process that removes impurities from a substance.
  • It is a broad term that encompasses techniques such as crystallization, distillation, filtration, etc.
• Recrystallization
  • Recrystallization is a specific type of crystallization used to further purify substances.
  • It involves dissolving the impure substance in a suitable solvent, followed by controlled cooling to form pure crystals.
• Applications of Crystallization
  • Used in the pharmaceutical industry to produce high-purity drugs.
  • Essential in the production of sugar, salts, and other food-grade substances.
  • Important in metallurgy for refining metals.