C4.2.2 Flame Tests

• Flame tests produce unique emission spectra for different metal ions.

  True
• To clean a nichrome wire, dip it into hydrochloric acid and heat it in a Bunsen burner flame until no color appears
• Steps to conduct a flame test

  1️⃣ Clean the nichrome wire

  2️⃣ Dip the wire into the compound

  3️⃣ Place the wire in the flame

  4️⃣ Observe the flame color

  5️⃣ Compare the color to known results
• The hottest part of a Bunsen burner flame is the inner cone
• What should you compare the observed flame color with during a flame test?

  Known flame test colors
• Flame tests can only identify positive metal ions.


  True
• Match the metal ion with its flame color:

  Calcium (Ca2+) ↔️ Orange-red

  Copper (Cu2+) ↔️ Green

  Barium (Ba2+) ↔️ Apple green
• Steps to set up a flame test properly

  1️⃣ Clean the nichrome wire

  2️⃣ Dip the wire into the sample

  3️⃣ Place the wire in the flame

  4️⃣ Observe the flame color

  5️⃣ Identify the metal ion
• Why should flame tests be conducted in a well-ventilated area?

  To avoid inhaling fumes
• Avoid touching the hot wire after the flame test to prevent burns
• What is a flame test used to identify?

  Metal ions
• Why is a flame test a quick and easy method for identifying metal ions?

  Requires small sample
• Match the metal ion with its flame color:

  Sodium (Na+) ↔️ Bright yellow

  Potassium (K+) ↔️ Lilac
• What flame color does sodium produce in a flame test?

  Yellow
• Which acid is used to clean the nichrome wire in a flame test?

  Hydrochloric acid (HCl)
• Safety goggles should be worn during a flame test to protect the eyes.


  True