What is the reaction of bile alum turning into anhydrous copper sulfate?

Bile alum is also called blue alum, copper alum, that is, copper sulfate pentahydrate Cuso4·5H2O, bile alum and anhydrous copper sulfate are both pure substances and compounds (crystal hydrate has a fixed composition and structure. Therefore, it is a compound and not a mixture. ）；150) The transformation of bile alum into anhydrous copper sulfate is a chemical change, cuso4·5h2o cuso4+5h20, (blue) (white) (when heated to 45, it loses two-molecule crystal water, 110 loses four-molecule crystal water, and at 150, it loses all crystal water to become anhydrous.)

However, anhydrous matter is also easy to absorb water and convert into copper sulfate pentahydrate. This reaction is the formation of two or more other compounds from one compound, which is a decomposition reaction; Moreover, this reaction needs to be heated, so it is not weathering; Weathering is the phenomenon in which crystalline hydrates lose their crystalline water at room temperature and in dry air. Weathering is a process of chemical change.

The phenomenon of heating crystalline hydrates to cause them to lose their crystalline water is not called weathering, but water. Moreover, during the weathering process, due to the characteristics of the crystal structure and the influence of external conditions, some crystals only lose part of the crystal water; Some crystals can lose all the crystal water; Some crystals first lose part of the crystal water, and then gradually lose all of the crystal water. It can be seen that weathering does not necessarily mean the loss of all crystal water.

Cholelum is copper sulfate pentahydrate, copper sulfate includes anhydrous copper sulfate and copper sulfate pentahydrate, inorganic compounds, the former is a white or off-white powder, the latter is a transparent dark blue crystal or powder, and the crystal water is lost by heating. Copper sulphate is both a fertilizer and a commonly used fungicide. Bordeaux liquid, copper soap liquid, and copper ammonium preparations are made of copper sulfate, quicklime, soap, and ammonium bicarbonate.

The physical and chemical properties of copper sulfate pentahydrate are transparent dark blue crystals or powders, with a solubility of 316 grams in 0 water, insoluble in ethanol, almost insoluble in most other organic solvents. In glycerin, it is Hu imitation jewel green, slowly weathered in the air, heated to lose two molecules of crystal water, Sun Tuan lost water under 110 and became white hydrate. When it contains impurities, it is yellow or green, and has no odor.

This product is very corrosive to iron. Copper sulfate is not only a fertilizer, but also a commonly used citrus agent. Bordeaux liquid, copper soap liquid, and copper ammonium preparations are made of copper sulfate, quicklime, soap, and ammonium bicarbonate.

The reaction of bile alum with concentrated sulfuric acid will produce white powder anhydrous copper sulfate, and anhydrous copper sulfate will rise high in reaction with water to form blue crystal copper sulfate pentahydrate.

Bile alum is a blue crystal, after adding concentrated sulfuric acid, concentrated sulfuric acid will absorb the crystal water in the bile alum, and it will become a white powder, that is, anhydrous sulfur copper veritate. Anhydrous copper sulfate changes from white to blue when exposed to water, and copper sulfate pentahydrate is generated.

Sulfuric acid dehydrates the bile alum crystals is a chemical reaction, not a physical reaction.

Concentrated sulfuric acid absorbs ready-made water, and what happens is a physical change. Concentrated sulfuric acid causes copper sulfate crystals to lose water, and what occurs is a chemical change that reflects the water absorption of concentrated sulfuric acid.

The difference between dehydration and water absorption of concentrated sulfuric acid:

Dehydration of concentrated sulfuric acid: concentrated sulfuric acid can make sucrose, starch, cellulose and other substances to lose water and carbonize, not because concentrated sulfuric acid absorbs the water contained in the organic matter (crystal water), but the atoms of hydrogen and oxygen elements in the composition of organic matter are taken out of the organic matter according to the ratio of 2 1 (water composition ratio) to form sulfuric acid hydrate, and at the same time the carbon in the composition of organic matter is left. In the case of concentrated sulfuric acid, it is dehydrated, and in the case of organic matter, carbonization occurs.

Water absorption of concentrated sulfuric acid: Concentrated sulfuric acid is water absorbent because it can combine with water to form hydrates of different compositions, and at the same time release heat. The hydrates of sulfuric acid include H2SO4·H2O, H2SO4·2H2O, H2SO4·4H2O, etc., and when the temperature of the sulfuric acid solution is lowered, these hydrates are precipitated in the form of crystals.

When concentrated sulfuric acid is diluted, a large amount of heat is released because the sulfuric acid combines with water to form a hydrate and emits more heat than it absorbs when its molecules diffuse. Water absorption, can play a role in a non-contact way, for example, through experiments: add a small amount of concentrated sulfuric acid to a test tube, put a layer of porous partition on it, put copper sulfate crystals on the partition, and then seal the test tube, leave it for a period of time to find that the copper sulfate crystals turn from blue to white.

Concentrated sulfuric acid absorbs water, which is not a chemical reaction for concentrated sulfuric acid and a dehydration reaction for bile alum.

This is the water absorption of concentrated sulfuric acid, which absorbs water molecules. Dehydration, on the other hand, refers to the removal of water molecules in the ratio of H and O, and is not really a water molecule.

Dehydration is a chemical change, and water absorption is a physical change. Is this true?

Analysis: Because dehydration removes the hydrogen and oxygen elements from the substance, new substances are generated, so it is a chemical change.

Water absorption is generally a physical change, however, when concentrated sulfuric acid absorbs the crystalline water in the substance, a chemical change occurs. For example, blue bile alum becomes a white solid when it encounters concentrated sulfuric acid, and a chemical reaction occurs, CuSO4·5H2O=CuSO4+5H2OIt should be noted here that crystalline water itself exists in the form of water molecules, so it belongs to water absorption.

Cholelum is copper sulfate pentahydrate (CuSO4·5H2O), blue, is crystal, and anhydrous copper sulfate (CuSO4) is white powder.

The blue crystals of bile alum are copper sulfate pentahydrate.

Cholelum. The crystal is a blue clump color crystal, adding concentrated sulfuric acid, concentrated sulfuric acid absorbs the crystalline orange water in the bile alum, and it becomes a round white powder, that is, anhydrous copper sulfate.

The equation is as follows: concentrated H2SO4 ==CuSO4 + 5H2O

Blue crystals, white powder.

It is dehydration, dehydration is a chemical change, the process of dehydration is a chemical change, this process generates new substances, such as concentrated sulfuric acid can remove hydrogen and oxygen in organic matter (including wood, cloth, **, sugars, etc.) in a ratio of 2 to 1 (in the form of water), and finally only carbon is left (sometimes there are other elements, or hydrogen and oxygen are not removed) (this process is called carbonization).or concentrated sulfuric acid can remove crystalline water from crystals with crystalline water (such as copper sulfate pentahydrate) to form crystals without crystallized water.

Water absorption, this process is a physical change (some are also chemical changes, such as concentrated sulfuric acid can absorb water vapor in the air around it, forming a series of hydrous compounds, on the other hand, sulfuric acid dissolves itself in the water in it, making itself thin).For example, sodium hydroxide solid has strong hygroscopicity, as long as a few minutes, it will absorb the water vapor around it, and the sodium hydroxide will dissolve itself in the absorbed water and become a concentrated solution of sodium hydroxide.