tests for gases and anions

• What paper do we use to test for chlorine gas?


  damp litmus paper
• What happens to damp litmus paper in the presence of chlorine gas?

  it bleaches white
• Why might litmus paper turn slightly red first in the test for chlorine?

  because chlorine is acidic
• How do you test for oxygen gas?

  Put a glowing splint inside a test tube with oxygen
• What is a positive test for oxygen?

  glowing splint relights
• What solution do we use to test for carbon dioxide?

  limewater
• How do you test for carbon dioxide?

  bubble gas through liimewater
• What's a positive test for carbon dioxide?

  cloudy limewater
• What's the test for hydrogen?

  squeaky pop
• Tests for anions give what?

  precipitates
• What do we use to test for carbonates?

  dilute acid (usually HCL)
• How do you test for carbonates?

  add dilute hcl and then bubble through limewater
• What's a positive test for carbonates?

  cloudy limewater
• What do you use to test for sulfates?

  dilute HCL

  barium chloride
• How do you test for sulfates?

  add few a few drops of dilute hcl

  add a few drops of barium chloride solution
• What's a positive test for sulfates?

  white barium sulfate precipitate
• What do you use to test for Halides?

  nitric acid

  silver nitrate
• Name the three halides tested for in a halide test.

  cl- (chloride)

  br- (bromide)

  i- (iodide)
• How do test for halide ions?

  add a few drops of dilute nitric acid

  add a few drops of silver nitrate solution
• What precipitate will be given for a positive test of chloride ions?

  white precipitate
• What precipitate will be given for a positive test of bromide ions?


  cream precipitate
• What precipitate will be given for a positive test of iodide ions?

  yellow precipitate