Kipp's apparatus: a simple device for an aquarium

The Kipp apparatus is a device that makes it possible to obtain gases. It is widely used in various laboratory studies, and in laboratories, chemists prefer to use cylinders as sources of gases. This is more convenient and safer, since in the event of improper operation of the Kipp instrument, hydrogen and flammable gases are likely to explode.

How does it work?

Kipp's Apparatus Works on a simple scheme, for example, if you need to get hydrogen. A grate with zinc granules is placed on the bottom of a medium-sized tank. It is filled with hydrochloric or sulfuric acid. If the tap on the off-gas tube is closed, the acid will be in the top funnel and the lower tank. When the tap is opened, the acid begins to flow out of the funnel and fill the bottom of the second tank. As a result of the reaction with zinc, hydrogen evolution takes place. This experience is often held in the chemistry lesson. After the experiment is over, the valve is closed, respectively, the hydrogen no longer leaves the apparatus.

What does it consist of?

The modern Kipp apparatus is two equal in volume reservoir with a plastic tube that enters the throat of the bottle. It is tightly closed on both sides with plastic stoppers, which ensures tightness. The upper part of the tube is equipped with a glued fitting, with which it is possible to remove carbon dioxide. Still below the tube has a stopper from the bottle, and the tightness is achieved due to the fact that a special ring of rubber or silicone is used. Under the cork is a wide cutout, where chalk or limestone is loaded. In order for the acid and these substances to interact well, the tube is perforated by openings allowing free contact of substances. Another tube, passing through both plugs, is needed in order to neutralize acid vapor in the off-gas.

How to get carbon dioxide?

Very often, a Kipp machine is used to supply CO2 _. As well as for obtaining carbon dioxide. To do this, just use chalk and acetic acid. Chalk should be a kind of pieces, not dust. The apparatus should be poured with a weak solution of acetic acid, the chalk is loaded from above, after which the tube itself is inserted inside the bottle. So CO _{2 is} released _{. It is} drained through the union, after which it passes through the soda solution and is fed into the aquarium. At the outlet of the tube you can put a non-return valve. That is, Kipp's apparatus works in such a way as to constantly maintain a constant gas pressure, which also depends on the depth of immersion in the spray bottle.

Where to find?

Many craftsmen prefer to assemble this unit with their own hands, especially since it is not so difficult to do it as it seems. At the same time, the stores sell a special Kipp machine for the aquarium, through which carbon dioxide is produced and the pressure is maintained at an automatic level. The very simple model of the device includes two plugs with fittings, a manometer, a needle pneumodrossel and acrylic tubules.

The rate of the chemical reaction will depend on how much calcium is contained in the chalk or limestone, its density and porosity. That is why, first you should select the concentration of acid for a small amount of water: the gas should be released in a small amount, but there should not be any frothing or bubbling. If the reaction proceeds slowly and the required amount of gas is not produced, it is worth reassembling the unit and using larger bottles. But the concentration of acid should not be increased, because it can, as a result, be too quickly neutralized.

In general, the device is inexpensive, since the reagents in the form of chalk and acids are quite cheap. And the device itself is very simple. The only problem can arise with the assembly - it must be done carefully and carefully to achieve reliability and tightness of the connection.