WARNING! This experiment is dangerous! You should NOT perform this at home. ONLY carry out this experiment, if you are a trained chemist, and you understand local safety and legal requirements, which are required to perform such experiments
- Obtain hydrogen chloride. Pour approximately 10 grams of sodium chloride into a flask and add 25 ml of concentrated sulfuric acid. Close the flask with a stopper equipped by a tap with a tube. Lower the other end of the tube into an empty liter flask. Hydrogen chloride is heavier than air, so the flask should be kept neck up while filling.
- Close the flask filled with hydrogen chloride.
- Fill a large evaporation dish with two liters of water.
- Dissolve a small amount of litmus in water.
- Replace the stopper of the flask with hydrogen chloride with a stopper equipped by tap with a tube.
- Attach the flask with hydrogen chloride on the stand upside down.
- Lower the other end of the tube into the evaporation dish with water.
- Observe the filling of the flask and the color change of the indicator from purple to red.