How to remove water chemistry, how to deal with scale removal chemistry?

Hello landlord! The three upstairs, you guys have a little problem. First of all, on the first floor, copper sulfate is generally used to test water, and its drying ability is not very strong, and it is not suitable for water removal.

On the second floor, is SO3 considered an acid gas? SO3 is always soluble in concentrated sulfuric acid. About anhydrous copper sulphate on the same floor.

Also, anhydrous calcium chloride is not that it cannot remove ammonia, but it cannot be used to dry ammonia, and the expression should be accurate. On the third floor, it is not just silica that can dry the gas, and its mechanism is the same as that of activated carbon, so it is required to be loose and porous. The above is pure**, non-complaining, I hope you will forgive me.

I don't know what angle the landlord is looking at this problem, after all, in addition to the water reagents, in addition to the above has been mentioned, there are anhydrous calcium sulfate, anhydrous magnesium sulfate, P2O5, molecular sieve, MG (CLO4)2, concentrated phosphoric acid and so on. Some are not suitable, and they are distilled under reduced pressure. But in terms of high school, it's much simpler.

Due to the influence of many things that have not been learned in high school, it is best for the landlord to remember what the desiccant cannot dry. (The following lists are all high school levels, which are very limited, but for example, there is still a lot to learn in college).

Concentrated sulfuric acid] can not dry alkaline gas, reducing gas, SO3.

Anhydrous calcium chloride] can not dry ammonia (it can form complex complexes with NH3), hydrogen halide (such as HCl, HBR, complex chemical reactions will occur, I didn't learn in high school).

Soda lime] cannot dry acid gas.

P2O5, concentrated phosphoric acid] cannot dry alkaline gases.

There are also some special, on the topic, the landlord should not be fixed-minded.

Well, that's it, if the landlord has a question, ask again!

Concentrated sulfuric acid (acidic, neutral gas, non-reducing gas), anhydrous copper sulphate (acidic, neutral gas), soda lime (alkaline, neutral).

Anhydrous calcium chloride (cannot remove ammonia).

Silicon dioxide, quicklime, anhydrous copper sulfate, anhydrous calcium chloride, concentrated sulfuric acid, activated carbon (adsorption of a small amount of water),

The addition of copper sulfate can remove water.

1. Edible vinegar to remove scale.

The main ingredient of limescale is calcium carbonate, and the acetic acid in vinegar reacts with it to produce minerals and carbon dioxide gas that dissolve in water. You can mix vinegar and water in a ratio of 1:10, then pour it into a kettle, boil it for about an hour, and finally brush it normally.

2. Remove limescale from egg shells.

Egg shells are also a great way to remove limescale from eating eggs, collect the remaining egg shells, twist them, put them in a limescale container, add most of the water and shake for about 10 minutes. The egg shell simply rubbed against the scale, so that the scale in the container was removed.

3. Use baking soda.

Pour baking soda powder into the kettle and add a small amount of water to make the baking soda powder into a paste, and gently wipe it with a cloth, and the scale will be easily wiped off.

4. Clean with starch.

Starch can also remove scale, as long as some starch content of food, such as yam, potato, etc., as long as their peeled skin into the scale kettle container, pour some water and leave for about half an hour, the adhesion of starch can remove the scale adhesion, but it is not for some hard scale and thick scale.

5. Noodle soup or rice water.

Noodle soup and rice water can be used to remove scale, you can pour the soup or rice water left over from the boiled noodles into the kettle, boil it with electricity, let it stand for half an hour, and wait for the scale to soften and can be easily wiped off.

Precautions: If the scale adheres to the heating surface of the thermal equipment, it will endanger the safe and economical operation of the thermal equipment. Because the thermal conductivity of limescale is very poor, it hinders heat transfer.

The heat absorbed by the furnace tube from the flame side cannot be well transferred to the water, and the cooling of the furnace tube is affected, so that the wall temperature rises, causing the furnace tube to bulge and cause a burst pipe.

The main component of limescale is calcium carbonate. Some acids can be added to dissolve calcium carbonate, such as vinegar, or hydrochloric acid. Calcium acetate and carbon dioxide, or calcium chloride and carbon dioxide, are formed, and the scale is dissolved.

Because the main ingredient of limescale is caco, it can be removed by reacting with vinegar. Pour white vinegar or vinegar into a pot, add water to boil, let stand for an hour and then scrub to remove limescale.

To remove scale, then you can use acid to decompose, decompose the scale, scale is generally insoluble in water substances, such as calcium carbonate, as long as acid can be added, the scale can be removed.

How to deal with limescale is very good after half an hour of baking soda and white vinegar.

Scale is a precipitate precipitated by the free calcium and magnesium in the water combined with acid roots to form calcium carbonate and magnesium carbonate during the heating process, mainly calcium salt.

The desiccant that removes water by chemical principle is listed below:

1. Acidic desiccant: containing concentrated sulfuric acid, phosphorus pentoxide, anhydrous copper sulfate, etc.;

2. Alkaline Lusundan desiccant: a mixture of solid caustic soda, lime and soda lime, sodium hydroxide and calcium oxide; Early disturbance.

3. Neutral desiccant: contains anhydrous calcium chloride and anhydrous magnesium sulfate.

Desiccants refer to substances that can remove water from moist substances, and are often divided into two categories: chemical desiccant, such as calcium sulfate and calcium chloride, etc., which are dried by combining with water to form hydrates; Physical desiccants, such as silica gel and activated alumina, are dried by physical adsorption of water.

The control of moisture is closely related to the yield of the product. In the case of food, under proper temperature and humidity, bacteria and moulds in food can multiply at an alarming rate, causing food to spoil, causing moisture and discoloration. Electronics can also cause metal oxidation due to high humidity, resulting in defects.

The use of desiccant is to avoid the occurrence of defective products caused by excess moisture.

The chemical equation for scale removal: CaCO3 + 2 HCl CACl2 + CO2 + H2O; mgco3 + 2 hcl → mgcl2 + co2 + h2o。

Limescale is usually formed by precipitating calcium carbonate or hard water with magnesium and calcium. To remove limescale, some chemicals such as hydrochloric acid can be used.

When hydrochloric acid is added to an area containing limescale, hydrogen ions (H+) in hydrochloric acid replace calcium ions (Ca2+) or magnesium ions (Mg2+) in the limescale to form soluble salts and at the same time release carbon dioxide gas

caco3 + 2 hcl → cacl2 + co2 + h2o

mgco3 + 2 hcl → mgcl2 + co2 + h2o

Among them, CaCO3 and MgCO3 represent calcium carbonate and hard water of magnesium and calcium, respectively. These equations represent the chemical equation for the reaction of hydrochloric acid with scale.

The main components of limescale are CaCO3 and a small amount of Mg(OH)2 In chemical experiments at the secondary school level, dilute hydrochloric acid (HCl) is used to remove scale, which is mainly used to clean utensils that are not easily corroded by hydrochloric acid, such as crucibles, test tube bottoms, and enamel jars. In life, we can remove limescale with sour vinegar or baking soda, etc.

The uses of hydrochloric acid are as follows:

1. Industry: Hydrochloric acid is used as a catalyst for various chemical reactions, such as the preparation of plastics, synthetic fibers, the production of metal salts, etc.

2. Medicine: Hydrochloric acid can be used to prepare drugs, such as cetirizine chloride, imatinib, etc., and can also be used to regulate gastric acid secretion, gastric diseases, etc.

3. Metallurgy: hydrochloric acid can be used to remove oxides and other impurities on the surface of metals to improve the quality and purity of metals.

4. Cleaning agent: hydrochloric acid can be used to clean metal surfaces, remove scale and oil, etc.

5. Laboratory: Hydrochloric acid is one of the most common chemical reagents in the laboratory, which can be used to adjust the pH of the solution, prepare the precipitate and other experimental operations.

1. White vinegar descaling method: pour white vinegar and water into the kettle at a ratio of 1:2, (250 ml of white vinegar is enough, that is, half a bottle of white vinegar bought from the supermarket is enough to use it at one time.)

Power off after boiling. Soak for more than 2 hours. If it is a stainless steel kettle, it is best to use this method before going to bed at night, boil it and mix it blindly, you can place it to soak overnight, and then pour out these vinegar water in the morning.

After being washed many times with clean water, the kettle is completely clean. If you have an aluminum kettle, boil the vinegar solution, leave it for 1 to 2 hours, and then clean it.

2. Lye descaling method: if the main component of scale is calcium sulfate, then pour the soda ash solution into the kettle and boil, and then place it for two hours, the scale can be removed. Then, wash the kettle with clean water several times.

3. Soda descaling method: fill the kettle with water, put in a little baking soda, and then boil, after a few minutes, the scale will automatically fall off. Clean the kettle with clean water several times and it will be completely clean.

4. Boiled potato descaling method: put 3 to 5 potatoes in the kettle and boil for a few hours, and the scale will fall off in pieces. Then, rinse it with clean water.

5. Boiled egg shell descaling method: boil the egg shell twice in a kettle. Then, clean the kettle with clean water to remove the limescale.