If the flame used to heat a flask is an orange color and blackens the bottom of the flask, what correction should you make to solve this problem?

Correct answer: D. Allow more air into the collar of the burner.

  • A. Move the flask farther from the flame.
  • B. Move the flask closer to the flame.
  • C. Allow less air into the collar of the burner.
  • D. Allow more air into the collar of the burner.

Explanation

An orange, sooty flame indicates incomplete combustion due to insufficient oxygen. Opening the collar of the Bunsen burner allows more air to mix with the gas, resulting in a hotter, cleaner, blue flame.

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About Experimental Techniques in Chemistry

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