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.
- E. The problem is in the supply of the gas, and you cannot fix it.
Explanation
One of the basic adjustments to a burner is to assure enough air is mixing with the gas to form a blue cone-shaped flame. With insufficient air, carbon deposits will form on the flask and the flame will be orange.
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About Experimental Techniques in Chemistry
Separation methods are selected according to differences in solubility, particle size, volatility and sublimation behaviour. Filtration and crystallisation separate insoluble or dissolved solids, sublimation isolates suitable volatile solids, distillation separates liquids by boiling point, and solvent extraction transfers a substance between immiscible solvents.
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