What acid and solid produce chlorine gas?

Answer 1

Hydrochloric acid will react with Manganese(IV) Oxide to produce Chlorine gas as well as Manganese(II) Chloride and water.

One may use other oxidizers in place of MnO2, such as Potassium Permanganate (KMnO4), but these tend to be more expensive or less common than Manganese Dioxide. Chlorine gas production A computer-generated graphic showing a chlorine generator similar in design to the above sketch may be seen below. The design the chlorine generators are essentially the same, but the computer-generated version gives a much more realistic depiction of what the glassware pieces look like and shows the use of an addition funnel to control the flow of hydrochloric acid into the flask containing manganese dioxide.

When ready to begin the reaction, add the Hydrochloric acid to the reaction vessel, then promptly place the stopper in the flask so as to direct any gasses produced out through the connected tubing.

In the main reaction vessel, the Hydrochloric acid will react with the Manganese Dioxide and produce Chlorine gas. Once the reactants are mixed, the chemical reaction will proceed spontaneously until the reaction exhausts the limiting reagent. The rate at which the reaction proceeds depends upon many factors including the concentration of the Hydrochloric acid and the particle size of the Manganese Dioxide. A higher concentration of acid and a finer MnO2 particle size will result in the reaction proceeding at a higher rate.

To gain greater control over the Chlorine production rate, one can optionally use an Addition Funnel, a piece of glassware designed to control the flow of a liquid from a container on top down into a flask placed underneath the funnel. A glass or rubber tube connects the top of the funnel to the flask below so as to allow a smooth flow of liquid by equalizing the pressure in both vessels while the value is open and liquid drains down into the flask. Utilizing an Addition Funnel, one can control the rate at which Hydrochloric acid flows into the flask containing the MnO2 powder, and thus the rate of Chlorine gas production.

The Chlorine gas produced during the reaction will fill the reaction vessel and then flow out through the tubing and into the next container, which is filled with water. The Chlorine gas stream emerging from the reaction vessel may also contain Hydrogen Chloride fumes from the Hydrochloric acid and also tiny particles of Manganese compounds from the reaction. As the Chlorine gas bubbles through the water, the impurities present in the gas stream dissolve and disperse into the water, leaving a greatly purified product emerging from water.

As the Chlorine gas bubbles through the water, some Cl2 will dissolve and react with the water to form Hypochlorous acid (HOCl) which will exhibit oxidizing properties not unlike household bleach, which is a Sodium Hypochlorite solution (NaOCl). One could produce Sodium Hypochlorite by dissolving Chlorine gas in a Sodium Hydroxide solution.

The Chlorine gas emerging from the water is "wet" due to the amount of water vapor present in the gas stream. One can dry the Chlorine gas and remove much of the water vapor by passing the gas stream into a drying tube filled with a deliquescentmaterial, such as Calcium Chloride (CaCl2). Calcium Chloride is extremely hygroscopic and will readily absorb water vapor from the air or, in this case, the surrounding Chlorine gas.

The end result of this process is a stream of relatively pure, dry, Chlorine gas.