How to make brine. General rules for the preparation of solutions

Crystal ... This word just breathes magic. I don't know what about the magical properties of crystals, but they definitely have a variety of useful physical properties. Crystals are widely used in modern electronics, optics and other fields of technology. And, of course, the crystals are just beautiful. They attract the eye with their regular shape and natural symmetry. And this applies not only to precious crystals, but also to crystals grown from improvised means.

We already know something about the crystalline state of matter from the article about. Now is the time to move on to practical exercises 🙂

The crystal growth experiment has a number of features. One of these features is the duration of the experiment. The point is that a good and beautiful, and, most importantly, a large crystal cannot be grown quickly. This takes time. That is why the experience of growing crystals for nine days developed in a section where you could observe the progress of the process and, perhaps, even conduct your experiment in parallel. This article is a summary of the information obtained during the experience. So, an instruction for those who want to grow a crystal themselves.

For this we need:

The container in which the crystal will grow. It is best if the container is transparent, such as a glass jar. In this case, it will be convenient to observe the progress of the process.
A small piece of cardboard to cut out the lid for the container
Funnel
Filter paper or any material that can be used to filter the solution. You can use a napkin.
Thread. It is better to take a thinner and smoother thread, for example, silk.
And, of course, the substance from which we will grow the crystal. The experiment uses copper sulfate. The crystal from it should turn out to be a beautiful blue color. In addition, it is quite easy to get copper sulfate - it is usually sold in any gardening store. If you did not manage to find copper sulphate or are simply too lazy to go to the store, then you can use any crystalline substance, for example, ordinary table salt or sugar.

Before starting the experiment, I must warn you, in case you want to repeat it, about personal safety measures. You will be working with chemicals that can harm you. Do not use food containers for your experience, use protective equipment (gloves, glasses), wash your laboratory glassware thoroughly. If chemicals come into contact with skin or eyes, rinse thoroughly with water. If swallowed, consult a doctor.

Well, the formalities are over, let's get started.

Day 1.

As I said before, growing crystals is a procedure that has some peculiarities. Another feature of this experiment, in addition to the duration, is the need to grow the so-called seed, i.e. a small crystal, on the basis of which a large crystal will grow. You can do without a seed, but in this case it is difficult to grow a beautiful single crystal. Therefore, it is better to grow the seed all the same, especially since there is nothing complicated in this.

Let's prepare a saturated solution.

Let's pour a little copper sulfate into a glass container (hereinafter I will talk about copper sulfate, since it is he who participates in the experiment, you use the substance that you managed to find).

Pour salt (and copper sulfate is sulfur-copper salt) with a little hot water. The use of hot water is compulsory because at elevated temperatures, the solubility of salts increases.

It is better to place the container in a water bath so that the solution does not cool ahead of time.

Stir the salt until dissolved, then add more salt and stir again. We repeat this until the salt stops dissolving in water.

Thus, we got a saturated salt solution.

Now the resulting solution needs to be filtered. This must be done so that no foreign particles, such as dust or impurities, remain in the solution. Foreign particles can serve as additional crystallization centers, i.e. other crystals will begin to form around them, but we do not need this. At this stage of the experiment, this is not very critical, but later the purity of the solution will be very important.

After it has been filtered, several salt crystals need to be thrown into the solution - seeds will begin to form on them.

Now the container needs to be placed in a place where a more or less constant temperature regime will be ensured (the window sill is great for this), and covered with something to prevent impurities from entering.

The solution will start to cool and oversaturate, i.e. salt will begin to become more in solution than it can dissolve at a given temperature. The salt will begin to crystallize, and the grains of salt that we added to the saturated solution will become the centers of crystallization. You will need to wait 2-3 days. After that, let's proceed to the next stage of the experiment.

Day 2.

It can be seen that crystals began to form at the bottom of the vessel.

Day 3.

Crystals have grown. In principle, they are large enough to be used as a seed, but I will try to sustain them for another day.

Day 4.

Well, enough time has passed, and we have formed a good material for seeding. It remains to choose a suitable candidate.

Pretty pretty already, isn't it? But we will not stop there and will continue our experiment.

It seems that the resulting mass of crystals is a monolith, but in fact it is not difficult to separate the crystals.

Try to choose the most correct crystal shape. I chose not the largest one available, but I liked its shape the most. The more correct the seed shape is, the more correct the crystal shape will be in the future. To make it easier to understand the size of the seed, I put a match next to it.

Now you need to tie a thread to the seed. As I wrote at the beginning of the article, it is better to take a thread that is less fleecy, so that secondary crystals do not form on its protruding villi. Do not use wire for suspension.

Now the thread with the dummy must be passed through the container lid and fixed on the back side. You need to fix it so that at any time it is possible to adjust the height of the suspension. For example, you can wind the excess thread on a match from the back side or secure the thread with a paper clip.

Now we need to prepare a fresh salt solution. It is done in the same way as for seeding: dissolving salt in hot water until it stops dissolving, filtering the solution. We put our seed into this fresh solution. Make sure that the seed does not touch the bottom and walls of the container, otherwise the crystal will begin to grow in an irregular shape.

And now we have two paths. The first one is more complicated. It requires more attention and effort. The fact is that the most beautiful and regular crystals are obtained when the crystallization process is slow. Therefore, we need to ensure smooth cooling of the salt solution. To do this, we need to place our container with a seed in thermal vessels, constantly monitor the temperature of the solution. In simple terms, there is a lot of fuss. But the reward for such efforts is worthwhile - the crystal will turn out to be as pure and correct as possible.

The second way is much easier. You have placed the seed in a hot solution and you can forget about it for a while, leaving the crystallization process to chance. With this method, the growing crystal may not be of ideal shape, but the growth process will be faster.

I chose the second path. In the end, after following a simpler path and gaining some experience, I can always do a more complex version of the experiment. In addition, you need to keep in mind that a quick version of the experience does not mean at all that it can be done in a couple of hours. Even with an accelerated experiment, the crystal will grow for several days. In the case of a long-term variant, the experiment may take 1 - 2 months.

But in both cases, you need to monitor the growth of the crystal. Once again, you do not need to take out the crystal and touch it - this may affect its shape. If side crystals begin to form on a crystal or thread, they must be carefully removed so that they also do not spoil the shape of the main crystal.

And one moment. If you dipped the seed into the solution, and it did not begin to increase, but quite the opposite, dissolves, then this means that you have prepared an unsaturated solution. The procedure for preparing the solution will have to be repeated.

So we continue to monitor the growth of the crystal. If you have any questions, you can contact me in the comments or through the form.

Day 5.

During the day, the crystal has grown significantly. In the photo there is a crystal in comparison with a match and a crystal - a substitute for the seed, which I left yesterday just in case.

However, as you can see, the shape of the crystal is not ideal, there are many defects. This is the result of rapid crystal growth. But I still like him 🙂

I renewed the solution as I had done before, and put the crystal there again. Since the size of the crystal increased significantly compared to the previous day, it was necessary to adjust the height of the suspension of the seed. The experiment continues.

Day 6.

The crystal has grown. I renewed the copper sulfate solution again.

Day 7.

The crystal barely fits into my glass! Do not forget to clean the thread from growing small crystals.

Day 8.

Day 9.

Well, here has come, I believe, the last day of the experiment. The latter is not because the crystal will not be able to grow further, but because it has become cramped in my laboratory glassware. We take out the crystal, cut a thread to its very root and blot it with napkins. We are one step away from admiring our work of art. The fact is that if you leave the crystal as it is, it will collapse pretty soon. To prevent this from happening, it must be "dressed" in a protective shell. The best option is to cover it with clear varnish. You can also place it in a hermetically sealed container, for example, in a jar. But it seems to me that the best option is to cover it with varnish. This will give it an additional shine, and it will be possible to observe it, as they say, live, and not through glass.

And now you can take a good look at the crystal. Of course, its shape was not perfect. But I deliberately chose the fast path of crystal growth instead of the quality one. In any case, I was pleased with the result. In nine days, the crystal has grown more than seven centimeters in length - a pretty good result!

I even wanted to give it a name. They give names to large and unique gemstones. For example, how the famous diamond was named "Count Orlov". My crystal, of course, is far from a diamond, but it is dear to me in its own way 🙂 Therefore, not without a share of humor, I decided to call the resulting seven-centimeter pebble Kid.

Good luck with your experiments!

Table salt in its pure form, or sodium chloride contains sodium 39.34, chlorine 60.66%,
In nature, table salt is found in the water of the seas, oceans, some lakes and underground sources, as well as in the form of layers of crystalline deposits. Depending on the nature of the deposits and mining methods, rock salt is distinguished, self-precipitated, cage, or pool, and evaporated.
Rock salt is mined from layers located at a particular depth underground. The nearest large deposits of rock salt are located in the area of Sol-Iletsk, Chkalovsk region and Artemovsk, Lugansk region of Ukraine. After the collapse of the USSR, Russia continued to buy salt from Ukraine. Self-precipitated salt is obtained from layers of salt that have settled on the bottom of lakes. Salt crystallization occurs in summer as a result of natural evaporation of lake water. Distinguish between current crystallization and old (root).
A significant amount of sedimentary salt itself is mined in Lake Baskunchak, in Lake Kuuli, in the lakes of Pavlodar region.
Sadochnaya, or pool salt, is extracted from its sediment, obtained in special pools, as a result of natural evaporation of the water of estuaries or some lakes, separated from the sea by narrow strips of the coast. Salt is mainly extracted from the water of estuaries or salt lakes of the Crimean region. Evaporated salt is obtained by evaporation of water from natural or artificial brines in special evaporators or vacuum evaporators. The extraction of evaporated salt is concentrated in Slavyansk, Usolye of the Irkutsk region and some other deposits.
The properties of table salt. Pure sodium chloride is obtained after crystallization in the form of colorless, regular cubic crystals with a specific gravity of 2.167 and a melting point of 800 °.
The specific gravity of natural salt ranges from 1.95 to 2.2, depending on the size of the crystals and the type of salt. During crystallization (precipitation), a part of the brine is retained inside the crystals, the more the larger the size of the precipitated crystals. The specific gravity of the brine is less than the specific gravity of pure crystals, therefore, the crystals of natural salt have a slightly reduced value of the latter. In rock salt crystals, brine inclusions are less than in the self-precipitated and pool salt of the current cage, therefore, the specific gravity of rock salt is higher than the specific gravity of self-precipitated and pool salt. For practical calculations, the specific gravity can be taken equal to 2.2.
Crystals of sodium chloride at a relative humidity above 75.5% absorb (absorb) moisture, and at a relative humidity below 75.5% they lose it. This property explains the change in the moisture content of salt when stored in air without hermetic packaging. Natural salts, especially self-precipitated and pool salts, containing admixtures of calcium and magnesium salts, have increased hygroscopicity in comparison with pure sodium chloride. When stored in a damp place or in riots in the air, the moisture content of the salt can reach without being accompanied by noticeable dissolution,
further absorption of moisture leads to partial dissolution of the salt. The hygroscopicity is largely due to the caking of salt during storage, that is, the adhesion of individual crystals to each other, as a result of which the salt is compacted into a solid homogeneous mass.
Wet salt, due to the stronger mutual adhesion of crystals caused by the presence of a saturated solution film on the crystals, is poorly dispersed; it is much more difficult to distribute it evenly by scattering it from a spatula over the surface of the layer of fish in vats than dry salt.
Ho wet salt (containing more than 4-5% moisture), in comparison with dry salt, upon stirring, forms dense, non-scattering lumps, which more firmly and in large quantities adhere to the fish. Therefore, when salting fish with preliminary mixing it with salt, it is better to use wet salt, while when salting with salt scattering over the layers of fish, it is better to use dry salt.
When salt is mixed with snow or finely crushed ice, melting of the latter is observed, since at temperatures above -21.2 °, salt and snow (ice) cannot be present at the same time. When ice (snow) melts in hectares of the environment, a large amount of heat is absorbed, and the preparation of cooling mixtures is based on this property. The lowest temperature, equal to -21.2 °, is obtained with displacements of 100 parts by weight of ice (snow) with 33 parts of salt (mixture composition: 24.4% salt and 75.6%, snow or ice).
Impurities in salt. Natural table salt, in addition to sodium chloride as the main compound, contains impurities of other salt-like compounds, most often salts of alkaline earth metals (calcium, magnesium), insoluble impurities and water. The water content depends on the storage conditions, while the content of salt-like impurities depends on the type of salt and the methods of its extraction. Table 1 shows the composition of the most common types of table salt in the Russian Federation.
Admixtures of magnesium and calcium salts during salting of fish are undesirable. In the presence of a significant amount of these impurities, the surface of the fish is greatly dehydrated, with dry salting, the formation of brine and the penetration of salt into the fish are delayed, and salted fish acquires a bitter taste. It was found that when the content of magnesium and calcium salts in table salt is more than 2%, the latter becomes unsuitable for salting fish. Among other soluble impurities, potassium chloride and sodium sulfate can be present in the salt, but usually in such insignificant quantities that they cannot have any effect on the speed of salting and the quality of the fish.

Insoluble substances are mixed with salt both during its extraction and during storage and transportation without packaging. With improperly organized harvesting, transportation and storage, the amount of insoluble impurities can be so great that during salting they envelop the surface of the fish and are difficult to remove even with thorough washing.
The composition of insoluble impurities includes both organic and inorganic compounds. Among the inorganic ones there can be sand, clay, coal, which fall mainly during storage and transportation, as well as oxides of iron, aluminum, carbonate salts of alkaline earth metals. Oxides of iron and aluminum are always present in rock salt, while calcium carbonate salts are found in salt obtained from sea water.
Self-precipitated and garden salts, in addition to contamination with impurities of organic and mineral origin, contain microorganisms that enter it from the brine of lakes and basins, as well as from the outside during storage at the fields, transportation and at places of consumption. The largest number of microorganisms entering salt from brine is in fresh salt; during storage (aging), their number decreases. Among these microorganisms, the most important are microorganisms from the group of micrococci, which have the ability to pigmentation. When the air temperature rises during storage on fish meat salted with such salt, a red color appears, accompanied by the appearance of mucus and the smell of protein breakdown products. Getting along with the salt to the fish industry enterprises, pigment-forming bacteria infect warehouses, storage areas for salt and evaporated rock salt in the warehouse.
Requirements for the quality of salt. The state standard for table salt admits the following lowest content of sodium chloride and the highest - impurities (Table 2).

The content of sodium sulfate in terms of dry matter is allowed:
a) for extra salt - no more than 0.2%;
b) for other varieties - no more than 0.5%;
Studies to study the effects of impurities contained in salt on the quality of finished salted products, carried out at different times, as well as the practice of salting, found that for different methods and types of salting, the limiting content of impurities in salt should be as follows (Table 3).
For salting, varieties of salt from extra (special salting of caviar) to grade I inclusive are quite suitable.
Salt grinding. Table salt, depending on the grinding (size of crystals), is divided into several numbers: 0,1,2,3. Extra salt has grind number 0; the highest and I grades - from No. 0 to 3: salt of the II grade - from No. I to 3. The characteristics of grindings are given in table. four.
Salt grinding or, in other words, the size of salt crystals is very important for salting fish: the rate of salt dissolution, its bulk density, and its hygroscopicity depend on their size.

The ratio of the surface of crystals to their volume, the so-called specific surface area, for large crystals is less than that of small ones. When dissolving, the same amount of salt goes into solution from each unit of the surface. But if this amount is attributed to a unit of volume or weight of crystals, then during the same period of time, salt in small crystals will dissolve much more than in large ones, since the total surface of the former is much larger than the latter. If it is required that the dissolution of the salt proceeds quickly, it is necessary to use a finer salt.
In addition, for uniform salting, the densest distribution of salt crystals is necessary so that the surface they occupy is close to the surface of the fish. This can be achieved only if, when determining the size of salt crystals, the surface of the fish or, more precisely, its specific surface (the ratio of the surface to the weight of the fish) is taken into account. For example, a Pacific herring weighing 200 g has a surface of 280 cm2, and weighing 22 g - 74 cm2. For a saturated salting, the first one requires 60 g of salt, and the second - 6 g; per 1 cm2 of surface should be distributed, respectively, 0.21 and 0.08 g. With the same size of crystals, the ratio of their contact surface to the total surface of large herring will be 2.5 times greater than that of small herring, since the amount of salt per 1 cm3 surface of fish, in the first case, 2.5 times more than in the second. Therefore, in order for the ratio of the contact surface to the total surface of the fish to be the same, for salting small herring, you should use finer salt, which has a larger surface for the same weight than coarse one.
In this regard, a second conclusion can be drawn: the lower the dosage of salt during salting, the lower the amount of salt crystals and the lower grind number should be used in order to have the greatest surface of contact of salt with fish
The use of very fine salt (grind nos. 0 and 1) in large quantities during salting can lead to undesirable results. Fine salt, having increased hygroscopicity, in comparison with larger crystals, with a lack of water on the fish for the formation of the first portions of brine, strongly dehydrates the integumentary tissues and thereby slows down the penetration of salt into the meat. This phenomenon is similar to dehydration of the fish surface due to the presence of large amounts of magnesium and calcium salts in the salt. In order to avoid intensive dehydration of the surface of the fish during saturated salting with dry salt, it is preferred to use table salt, consisting of mixtures of crystals of various sizes - up to 3-4 mm inclusive (grinding No. 2). In such a mixture, there are enough crystals of 1 mm or less, which increase the contact surface of salt with fish, and, quickly dissolving, form the first portions of brine without strong tissue dehydration. Subsequent portions of the brine are formed due to the dissolution of crystals with a large surface; Observations show that in the presence of a mixture of crystals of various sizes in the salt, dissolution in the fish-salting dishes proceeds normally, in the presence of the beginning of the salting process.
Volumetric weight of salt. To account for the amount of salt in salt storages and its current consumption, it is useful to know the bulk weight of the salt. The bulk density of bulk products is the weight of a unit of volume (1 m3) in tons or kilograms. The bulk density depends on the specific gravity of the product, the size of its particles and the ratio of their various sizes, moisture content and the degree of pressure of the overlying layers on it. For various types of salts used in the fishing industry, the bulk density ranges from 1038 to 1365 kg (Table 5). Bulk dog salt of the same species and region of extraction is greater in small ones than in large ones.

Properties of sodium chloride solutions. Sodium chloride is soluble in water, and the solubility, ie, the limiting amount required to obtain a saturated solution, changes slightly with increasing temperature (Table 6).

DI. Mendeleev for the temperature range from 0 to 108 ° deduced the following formula for determining the limiting dissolution of salt in 100 g of water

where t is the temperature in degrees Celsius
Solubility can be expressed in grams of sodium chloride in 100 g of solution or in grams per 100 g of water. There is a fairly simple relationship between these values. Let us denote the salt content (in g) in 100 g of the solution through c, and the amount of salt (in g) dissolving in 100 g of water to obtain a solution with the specified salt content through a. It is obvious that from grams of salt it dissolved in (100-s) g of water, in 100 g of water it will dissolve:

Knowing a, we can calculate c by the formula:

The solubility of sodium chloride in 100 g of water, calculated by the formula (2), is given in table. 6.
Almost the same solubility of sodium chloride within the temperature range from 0 to 20 ° is important for the practice of salting, since it is not necessary to change the dosage of salt with a change in temperature within these limits.
Sodium chloride solutions are heavier than water and their specific gravity is more than one. For a temperature of 15 °, the specific gravity of the solution, related to the specific gravity of water at 4 °, can be calculated using the following formula of D.I. Mendeleev:

where c is the concentration of salt in the solution as a percentage of its weight.To determine the specific gravity, hydrometers or densimeters are used, on the scale of which there are numbers showing the value of the specific gravity at 20 ° in relation to the specific gravity of water at 4 °, taken equal to one. When using conventional hydrometers (densimeters), the specific gravity is determined with an accuracy of 0.0! and only with the presence of special hydrometers it is possible to increase the determination accuracy to 0.001.
In the recent past, along with hydrometers and densimeters, hydrometers with a conventional scale of Bohme degrees were used to determine the specific gravity. 0 ° of this scale corresponds to the depth of immersion in clean water, and 10 ° to 10% sodium chloride solution. To convert Baume degrees to specific gravity, use the following formula:

where n is the exponent of the Bohme hydrometer.
Table 7 brought the specific gravity of salt solutions at 0 °, 10 °, 20 ° and the corresponding values of salt concentration as a percentage of the weight of the solution.
When determining the specific gravity of a solution whose temperature does not coincide with the calibration temperature of the ariometer to bring the found specific gravity to a temperature of 20 °, the following formula can be used:

where: d4v20 - specific gravity at 20 °;
d4v1 - the same at the measurement temperature t;
0.0004 is the coefficient of temperature change in the chargeability of the salt solution.
The boiling point and freezing point of sodium chloride solutions depends on the concentration of the latter: the more concentrated the solution, the higher the boiling point and the lower the freezing point (Table 8).

When the saturated solution is cooled below 0 °, an excess of dissolved salt first precipitates, as a result of which the salt concentration in the solution decreases, and, after it decreases to 24.4%, the solution freezes at a temperature of -21.2 °. Salt precipitated at temperatures below 0 ° has the composition NaCl 2H20. that is, it crystallizes with two water molecules. With a further increase in concentration, the freezing point does not decrease, but increases, and not water is released in solid form, but salt. The temperature of -21.2 ° is the lowest of all possible freezing temperatures of sodium chloride solution.
The reaction of solutions of sodium chloride and natural salts is almost neutral. According to the standard for salt, the common food reaction of an aqueous solution of salt to litmus should be neutral or close to it.
A saturated salt solution at a relative humidity of 75.5% does not lose moisture by evaporation and does not absorb it from the air. This equilibrium relative humidity is called the hygroscopic point of saturated salt solution and is approximately equal to the hygroscopic point of solid salt.
Brine concentrators. In addition to crystalline salt, a large amount of aqueous solutions of its brine or artificial brine is consumed during salting. To prepare them, it is advisable to use special installations - brine concentrators, the performance of which can vary over a wide range, A brine concentrator of small capacity is a wooden vessel of cylindrical or conical shape, about 60-70 cm high, in which a grate is fixed at a distance of 10-15 cm from the bottom, covered with cloth (burlap) or a clean mesh, serving to place a layer on it with a height of at least 50-40 cm.
There is a drain pipe directly near the bottom of the brine concentrator. Water enters the upper part through a perforated pipeline or through a perforated surface and is evenly distributed over the entire cross section of the salt layer in the brine concentrator. By adjusting the flow rate of water and the height of the salt layer, it is easy to achieve the outflow of a saturated brine having a specific gravity of 1.2.
To quickly obtain large quantities of brine, we offer a brine concentrator, into which water is pumped into the lower part under pressure, and the brine flows out of the upper part.
In this case, the salt layer is maintained at a height of at least 1 m, so that full saturation occurs with a single movement of water through the salt layer.

To the question Tell the idiot how to make a crystal from salt correctly? I dissolved in water to a fig of salt (in warm). given by the author XMatvey the best answer is Pour edible salt into a glass and leave for 5 minutes, stirring first. During this time, the glass of water will heat up and the salt will dissolve. It is advisable that the water temperature does not drop yet. Then add more salt and stir again. Repeat this step until the salt dissolves and settles to the bottom of the glass. We got a saturated salt solution. Pour it into a clean container of the same volume, while getting rid of excess salt at the bottom. Choose any larger crystal of table salt you like and place it on the bottom of a glass with a saturated solution. You can tie the crystal by a string and hang it so that it does not touch the walls of the glass. Now you have to wait. Within a couple of days, you can notice a significant growth for the crystal. It will increase every day. And if you do the same thing again (prepare a saturated salt solution and dip this crystal into it), then it will grow much faster (remove the crystal and use the already prepared solution, adding water and the necessary portion of edible salt to it). Remember that the solution must be saturated, that is, when preparing the solution, salt should always remain at the bottom of the glass (just in case). For information: in 100 g of water at a temperature of 20 ° C, approximately 35 g of table salt can dissolve. As the temperature rises, the solubility of the salt increases.
This is how the crystals of table salt are grown (or crystals of salt, the shape and color of which you prefer)

Answer from 22 answers[guru]

Hey! Here is a selection of topics with answers to your question: Tell the idiot how to make a crystal from salt correctly? I dissolved in water to a fig of salt (in warm).

Answer from Grow up[newbie]
you need to tie a thread to the salt crystal and lower it to the bottom of the glass so that it does not touch its walls, and leave it for several days every day the crystal will grow.

Answer from Hair[guru]
Salt already consists of crystals, but small.

Answer from Kashid Gabbasov[guru]
The maximum solubility is at about 41 C (a funny arc of solubility, you heat further and dissolve less). Pull off a hair of the girl's beloved and immerse the largest crystal in the air. They grow very large. I don't remember how many grams per liter. Nitrous silver record. 1700 per liter.

Answer from I-beam[guru]
"... Choose any larger crystal of table salt you like and put it on the bottom of a glass with a saturated solution. You can tie the crystal by a string and hang it so that it does not touch the walls of the glass. Now you need to wait. After a couple of days you can notice a significant crystal growth. Every day it will increase ... "
We quote all!

Answer from Andrey Shahnov[guru]
woolen thread hanging down the center of the glass

Answer from Peacemaker With Bazooka[guru]
Salt crystals - the growing process does not require any special chemicals. We all have table salt (or table salt) that we eat. It can also be called stone - everything is the same. Crystals of sodium chloride NaCl are colorless transparent cubes. Let's start. Dilute the sodium chloride solution as follows: pour water into a container (for example a glass) and put it in a saucepan with warm water (no more than 50 ° C - 60 ° C). Of course, ideally, if the water does not contain dissolved salts (that is, distilled), but in our case, you can use tap water. Pour edible salt into a glass and leave for 5 minutes, stirring first. During this time, the glass of water will heat up and the salt will dissolve. It is advisable that the water temperature does not drop yet. Then add more salt and stir again. Repeat this step until the salt dissolves and settles to the bottom of the glass. We got a saturated salt solution. Pour it into a clean container of the same volume, while getting rid of excess salt at the bottom. Choose any larger crystal of table salt you like and place it on the bottom of a glass with a saturated solution. You can tie the crystal by a string and hang it so that it does not touch the walls of the glass. Now you have to wait. Within a couple of days, you can notice a significant growth for the crystal. It will increase every day. And if you do the same thing again (prepare a saturated salt solution and dip this crystal into it), then it will grow much faster (remove the crystal and use the already prepared solution, adding water and the necessary portion of edible salt to it). Remember that the solution must be saturated, that is, when preparing the solution, salt should always remain at the bottom of the glass (just in case). For information: in 100 g of water at a temperature of 20 ° C, approximately 35 g of table salt can dissolve. As the temperature rises, the solubility of the salt increases.
This is how the crystals of table salt are grown (or crystals of salt, the shape and color of which you prefer)
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