Identifying ions

• What is the title of the practical discussed by Mrs. Pierce Dent?

  Identifying ions
• Which GCSEs require the practical on identifying ions?

  Separate GCSEs
• What method is used to identify metal ions in the practical?

  Flame tests
• Which metal ions are tested in the flame tests?

  Potassium, lithium, calcium, copper, sodium
• What is the purpose of using nichrome wire in flame tests?

  To hold the metal in the flame
• How is potassium chloride prepared for the flame test?

  Dip nichrome wire in potassium chloride solution
• What color flame does potassium produce in the flame test?

  Lilac purple
• How can the orange color in the flame be reduced when testing potassium?

  By using blue glass
• What color flame does lithium produce in the flame test?

  Crimson red
• How does the flame color of calcium differ from lithium?

  Calcium gives an orange red flame
• What color flame does copper produce in the flame test?

  Green
• Why is sodium tested last in the flame tests?

  It can interfere with other colors
• What color flame does sodium produce in the flame test?

  Bright yellow
• What is the first test performed on non-metal ions?

  Adding hydrochloric acid
• What gas is produced when hydrochloric acid reacts with sodium carbonate?

  Carbon dioxide
• What is the result of adding hydrochloric acid to sodium sulfate?

  No significant reaction occurs
• What precipitate forms when barium chloride is added to sodium sulfate?

  White precipitate of barium sulfate
• What color precipitate does silver nitrate produce with sodium chloride?

  White precipitate
• What color precipitate does silver nitrate produce with sodium bromide?

  Cream precipitate
• What color precipitate does silver nitrate produce with sodium iodide?

  Yellow precipitate
• What tests can be used to identify metal and non-metal ions in solutions?

  • Flame tests for metal ions
  • Hydrochloric acid for carbonate ions
  • Barium chloride for sulfate ions
  • Silver nitrate for halide ions
• What are the flame colors associated with each metal ion tested?

  • Potassium: Lilac purple
  • Lithium: Crimson red
  • Calcium: Orange red
  • Copper: Green
  • Sodium: Bright yellow
• What are the precipitate colors formed with silver nitrate for halide ions?

  • Chloride: White precipitate
  • Bromide: Cream precipitate
  • Iodide: Yellow precipitate
• What is the significance of cleaning the nichrome wire between tests?

  • Prevents contamination of metal ions
  • Ensures accurate flame color observation
• What is the role of hydrochloric acid in identifying ions?

  • Tests for carbonate ions by producing fizzing
  • Used in conjunction with barium chloride for sulfate ions
• What is the role of barium chloride in identifying ions?

  • Tests for sulfate ions by forming a white precipitate
• What is the role of silver nitrate in identifying ions?

  • Tests for halide ions by forming precipitates
• What is the importance of using blue glass during flame tests?

  • Reduces interference from orange flame colors
• Why is it important to differentiate between the colors of lithium and calcium flames?

  • To avoid confusion in exam answers
• What is the significance of the order of tests performed on non-metal ions?

  • Ensures accurate identification without interference
• How can unknown solutions be identified using the tests discussed?

  • By combining flame tests and chemical reactions