Carbonate, hydroxide and bicarbonate of calcium

Calcium... What do you know about him? "This is metal," - many will answer. And what calcium compounds exist? With this question everyone will begin to scratch in the back of the head. Yes, there are few knowledge about the latter, and about calcium itself, too. Okay, we'll talk about it later, but today let's analyze at least three of its compounds - carbonate, hydroxide and calcium bicarbonate.

1. Calcium carbonate

It is a salt, which is formed by calcium and the residue of carbonic acid. The formula of this carbonate is CaCO₃.

Properties

It has the appearance of a white powder, insoluble in water and ethyl alcohol.

Preparation of calcium carbonate

It is formed by calcination of calcium oxide. Water is added to the latter, and then carbon dioxide is carried through the resulting solution of calcium hydroxide. The reaction products are the desired carbonate and water, which are easily separated from each other. If it is heated, then there will be a splitting, the products of which will be carbon dioxide and quicklime. By dissolving this carbonate and carbon monoxide (II) in water, calcium hydrogen carbonate can be obtained. If carbon and calcium carbonate are combined, the products of this reaction will be calcium carbide and carbon monoxide.

Application

This carbonate is chalk, which we regularlywe meet in schools and other primary and higher educational institutions. Also they whitewash the ceilings, paint tree trunks in the spring and alkalize the soil in the gardening industry.

2. Calcium bicarbonate

It is a salt of carbonic acid. Has the formula Ca (NSO)₃)₂.

Properties

It dissolves in water, like all hydrocarbonates. However, it makes it tough for a while. In living organisms calcium bicarbonate and some other salts with the same residue have the function of regulators of constancy of reactions in the blood.

Receiving

It is obtained by the interaction of carbon dioxide, calcium carbonate and water.

Application

It is contained in drinking water, where its concentration can be different - from 30 to 400 mg / l.

3. Calcium hydroxide

The formula is Ca (OH)₂. This substance is a strong base. In various sources, it can be called slaked lime or "pushonka."

Receiving

It forms when calcium oxide and water interact.

Properties

It has the appearance of a white powder, slightly solublein water. With increasing temperature, the numerical value of solubility decreases. It also has the ability to neutralize acids, this reaction produces the corresponding calcium salts and water. If you add to it dissolved in water carbon dioxide, you get all the same water, and even calcium carbonate. With continued bubbling CO₂ calcium bicarbonate will form.

Application

They are littered with rooms, wooden fences, and alsocover the rafters. With the help of this hydroxide, a calcareous mortar, chlorine lime, special fertilizers and silicate concrete are prepared, and the carbonate hardness of the water is also eliminated (soften the latter). Through this substance, causticization of potassium and sodium carbonates is carried out, the root canals of the teeth are disinfected, the skin of the skin is healed and some plant diseases are cured. Calcium hydroxide is also known as food additive E526.

Conclusion

Now you understand why in this article Idecided to describe these three substances? After all, these compounds "meet" each other during the decomposition and receipt of each of them. There are many other related substances, but we'll talk about them some other time.