Mixtures

• What are the different methods to separate mixtures mentioned in the study material?

  Filtration, crystallisation, simple distillation, fractional distillation, and chromatography
• Why does the method chosen to separate mixtures depend on the type of mixture?

  Because different mixtures have different properties that require specific separation techniques
• What is the definition of a pure substance in chemistry?

  • Consists only of one element or one compound
  • Different from everyday meaning of 'pure'
• What does the term 'element' refer to in chemistry?


  An element is a substance made of one type of atom only
• What is a compound in chemistry?

  A compound is a substance formed by the chemical union of two or more elements
• How is a mixture defined in chemistry?

  A mixture consists of two or more substances that are not chemically joined together
• What happens to the chemical properties of substances in a mixture?

  Being part of a mixture does not change the chemical properties of the substances
• What are the characteristics of the processes used to separate mixtures?

  • Mixtures can be separated by physical processes
  • No chemical reactions occur
  • No new substances are made
• What is the significance of the figure caption mentioned in the study material?

  It indicates that the components of a mixture can be separated without chemical reactions
• What are the types of substances that can be found in a mixture?

  • Elements
  • Compounds
  • Both elements and compounds
• What are some methods used to separate mixtures?

  Filtration, crystallisation, simple distillation, fractional distillation, and chromatography
• What factors determine the method chosen for separating mixtures?

  • Type of mixture
  • Desired purity of components
  • Physical properties of the substances
• What is the purpose of filtration?

  To separate an insoluble solid from a liquid using a physical barrier
• What is an example of an insoluble solid?

  Sand is insoluble in water
• How does filtration work?

  It uses filter paper with tiny holes to allow small molecules and dissolved ions to pass through while retaining larger particles
• Describe the process of filtration step by step.

  1. Prepare a filter funnel with filter paper.
  2. Pour the solid-liquid mixture into the funnel.
  3. The liquid drips through while solid particles are caught in the filter paper.
• What is crystallisation used for?

  To produce solid crystals from a solution by evaporating the solvent
• What happens to the solvent during crystallisation?

  The solvent evaporates, leaving behind solid crystals
• How can you obtain copper sulfate crystals from a solution?

  By warming the copper sulfate solution to evaporate some solvent
• What are the steps to obtain large, regularly shaped crystals from crystallisation?

  1. Place the solution in an evaporating basin.
  2. Warm the solution over a boiling water bath.
  3. Stop heating when crystals form around the edge.
  4. Cool the remaining solution and pour away excess liquid.
  5. Dry the crystals using a warm oven or filter paper.
• What is the role of a Bunsen burner in crystallisation?

  To heat the solution in the evaporating basin
• What is a crystal?

  A solid containing particles joined together in a regular arrangement
• What is a solution made of?

  A mixture formed by a solute and a solvent
• What are some methods used to separate mixtures?

  Filtration, crystallisation, simple distillation, fractional distillation, and chromatography
• What is the definition of a solvent?

  The liquid in which the solute dissolves to form a solution
• What factors determine the method chosen for separating mixtures?

  • Type of mixture
  • Desired purity of components
  • Physical properties of substances (e.g., boiling points)
• What is evaporation?

  The process in which a liquid changes state and turns into a gas
• What is simple distillation used for?

  To separate a solvent from a solution
• What is the significance of the filter paper in filtration?

  It has tiny holes that allow small particles to pass while blocking larger ones
• Why is simple distillation useful for producing pure water from seawater?

  Because the dissolved salt has a much higher boiling point than the water
• How does crystallisation differ from filtration in separating mixtures?

  Crystallisation produces solid crystals from a solution, while filtration separates solids from liquids
• What happens to the solvent during simple distillation?

  The solvent vaporizes, moves away, and is condensed back into liquid
• What occurs to the remaining solution during simple distillation?

  The remaining solution becomes more concentrated as the solvent decreases
• Describe the process of simple distillation.

  1. Heat the solution (e.g., salty water).
  2. Solvent vaporizes.
  3. Vapor cools and condenses in the condenser.
  4. Collect the condensed solvent in a beaker.
  5. Solute (e.g., salt) remains in the original container.
• What is fractional distillation used for?

  To separate different liquids from a mixture of liquids
• How does fractional distillation work?

  It separates liquids based on their different boiling points
• What is an example of a mixture that can be separated by fractional distillation?

  Crude oil
• What are fractions in the context of fractional distillation?

  Fractions are parts of the original mixture with similar boiling points
• What happens to vapors during fractional distillation?

  Vapors rise through a column that is hot at the bottom and cooler at the top
• How are different liquids collected during fractional distillation?

  By collecting them from different parts of the column or by continuing to heat the mixture