Purity and Formulations

• What is meant by a formulation in chemistry?

  A complex mixture designed as a useful product
• What can a pure substance be?

  A single element or a single compound
• How can we determine if a substance is pure?

  By measuring its melting and boiling points
• What happens to the temperature of a pure substance during melting?

  The temperature remains fixed at a specific point
• What is the melting point of pure water?

  0 degrees Celsius
• What is the boiling point of pure water?

  100 degrees Celsius
• How does the melting and boiling point of an impure substance differ from that of a pure substance?

  They occur over a range of temperatures
• What are the characteristics of a pure substance's melting and boiling points?

  • Melting point is fixed at a specific temperature
  • Boiling point is fixed at a specific temperature
  • Impurities cause a range of temperatures
• What is the shape of the graph for a pure substance's melting and boiling points?

  It has a specific fixed temperature shape
• Why are the quantities of each component in a formulation carefully measured?

  To ensure the product has desired properties
• What does a similar shape graph for any impure substance indicate?

  It shows melting and boiling over a range