E-liquids - a guide for beginners. liquid state

We tend to think that liquids have no shape of their own. This is not true. The natural shape of any liquid is a sphere. Usually, gravity prevents the liquid from taking this shape, and the liquid either spreads thin layer, if poured without a vessel, or takes the form of a vessel, if poured into it. Being inside another liquid of the same specific gravity, the liquid, according to the law of Archimedes, “loses” its weight: it seems to weigh nothing, gravity does not act on it - and then the liquid takes its natural, spherical shape.
Provence oil floats in water but sinks in alcohol. Therefore, it is possible to prepare such a mixture of water and alcohol in which the oil does not sink and does not float. By injecting a little oil into this mixture by means of a syringe, we will see a strange thing: the oil is collected in a large round drop that does not float or sink, but hangs motionless a vessel of any shape, but placed inside a vessel filled with water with flat walls)].

Rice. Oil inside a vessel with diluted alcohol is collected in a ball that does not sink or float (Plato's experiment).

Rice. If the oil ball in alcohol is rapidly rotated with the help of a rod stuck into it, a ring is separated from the ball.

The experiment must be done patiently and carefully, otherwise you will get not one big drop, but several smaller balls. But even in this form, the experience is quite interesting.
This, however, is not all. Having passed a long wooden rod or wire through the center of the liquid oil ball, they are rotated. The oil ball takes part in this rotation. (The experiment works better if you put a small cardboard circle moistened with oil on the axis, which would remain entirely inside the ball.) Under the influence of rotation, the ball first begins to flatten, and then after a few seconds separates the ring from itself. Breaking apart, this ring forms not shapeless pieces, but new spherical drops that continue to circle around the central ball.

Rice. Simplifying the Plateau experience.

For the first time this instructive experience was made by the Belgian physicist Plateau. Here the Plateau experience is described in its classical form. It is much easier and no less instructive to produce it in a different form. A small glass is rinsed with water, filled with olive oil and placed on the bottom of a large glass; so much alcohol is carefully poured into the latter so that the small glass is completely immersed in it. Then, along the wall of a large glass from a spoon, carefully add a little water. The surface of the oil small glass becomes convex; convexity gradually increases and with enough poured water rises from the glass, forming a ball of rather considerable size, hanging inside a mixture of alcohol and water (Fig. 58).
In the absence of alcohol, this experiment can be done with aniline - a liquid that is heavier than water at ordinary temperatures, and lighter than water at 75 - 85 ° C. By heating the water, we can therefore cause the aniline to float within it, whereby it takes the form of a large spherical drop. At room temperature a drop of aniline is balanced in a salt solution [From other liquids, orthotoluidine is convenient - a dark red liquid; at 24° it has the same density as salty water, into which orthotoluidine is immersed].

Liquids are substances in a state intermediate between solid and gaseous. They are characterized by high mobility of particles and small free space between them. Hence, there are two main properties of liquids: in contrast to solids they easily change shape, but, like solids, they have very little compressibility.

The liquid state is intermediate between gaseous and solid in many ways. The viscosity of liquids is much less than the viscosity of solids and much greater than the viscosity of gases. The distance between gas molecules is several times greater than the size of the molecules; In a liquid, the molecules are placed close to each other. Therefore, the density of a liquid is several orders of magnitude greater than the density of gases (at normal pressure) and almost does not differ from the density of solids; Thus, the density of metals during melting changes by an average of 3%. In terms of internal energy, a liquid is usually much closer to a solid than to a gas; the heat of fusion, as a rule, does not exceed 10% of the heat of vaporization. The heat capacity of a liquid near the melting point is also close to the heat capacity of a solid.

However, the shape of a liquid body, like a gas, is determined by the shape of the vessel.

Unlike crystals, there is no long-range order in a liquid, but only short-range order. This means that there is a certain order in the arrangement of molecules, but if in crystals this order is the same in all areas of the crystal, then in a liquid it can be in various areas various. A direct consequence of the lack of long-range order is that the properties of a fluid are the same in all directions; they say that it is isotropic, unlike a crystal, which is anisotropic (the Greek words "isos" mean "equal", "same", "anisos" - "unequal", "tropos" - "direction"). Liquids are a very wide class of substances: from simple ones, which are really isotropic and lack long-range order, to complex, polymeric ones, which contain elements of long-range order and anisotropy.

The most characteristic molecular property of a liquid is surface tension. It is due to the fact that the molecules in the surface layer are in special condition compared to the molecules inside the liquid. The latter are uniformly surrounded on all sides by their neighbors, but the molecules on the surface are not. Therefore, the resultant of the cohesive forces tends to draw the molecules of the surface layer inside, and to increase the surface, for example, to stretch the liquid film, work must be expended on extracting the molecules from the inside to the surface.

The work done to form a unit surface is called surface tension. Numerically, surface tension is equal to the force acting per unit length of the line that limits the surface of the liquid and tends to reduce this surface. Under the action of surface tension, the liquid takes the form of a ball, which has the smallest surface for a given volume. In Plato's famous experiment, a drop of one liquid, placed in another liquid of the same density, which does not mix with the first, took on a spherical shape. This is also the form of small droplets of mercury on a glass plate, or droplets of water on a paraffin-coated glass surface. Mercury does not interact with glass, does not wet it, and water does not wet paraffin. The forces of interaction between the molecules of a liquid and a solid cause the spreading, for example, of a drop of water on a degreased glass, the force of gravity flattens the drop, and the stronger, the larger its size. You can read more about this in Ya. E. Geguzin's book "The Drop" (M.: Nauka, 1973).

The viscosity of the liquid increases with decreasing temperature and increases abruptly during crystallization. When the liquid is supercooled below the melting point, the viscosity also increases greatly, which slows down crystallization and contributes to the appearance of an amorphous glassy state. When heated, liquids usually expand, with the exception of water (in the range from 0 to ).

As shown by the Dutch scientist J. Van't Hoff, the molecules of a solute in a liquid solution behave like a gas in the same volume and exert a specific pressure, which he called osmotic. Osmotic pressure was first observed in 1748 by the French physicist Nollet in a well-known experiment with a semipermeable septum made of a bull bladder.

The bubble tightened the lower end of vessel A with a solution of sugar in water, immersed in vessel B with clean water. Water molecules can pass through the bubble, but much larger sugar molecules cannot. As a result, the level of the solution in vessel A rises until the hydrostatic pressure of the rising column of liquid is equal to the osmotic pressure of the dissolved sugar.

The osmotic pressure is high and reaches tens of thousands of atmospheres in dilute solutions. Effects associated with osmotic pressure, play an important role in nature (penetration nutrients from soil to plants, metabolism in living organisms).

I once experimented with an unsuspecting and unexpecting friend. I mixed up the new liquid flavor and gave it a try. “Delicious, but nothing amazing,” he said. After a while, I treated him to the same liquid, saying: "Try, great taste! And he really liked the taste too. The only difference was that it was the same liquid. He felt the difference in taste only because our perceptions often cloud our judgment and objectivity.

The opinions of vapers about the infusion of liquids are divided. Some people think it's a waste of time, while others say that insistence is of the utmost importance. Let's try to figure out what's the matter? In the perception of taste or in the actual difference in taste after the infusion? We will test blindly and resolve these issues once and for all. But first, let's figure out what the infusion of liquids is, what processes take place during this period, and consider several methods.

• Infusion. What is infusion of liquids? This is a way to improve the taste. Usually the liquid is infused in a static state, sometimes shaken and sometimes agitated (depending on the method) so that the liquid comes into contact with air. It's like with good wine - the older the better. Further in the article, we will consider a number of techniques aimed at accelerating the time of infusion of liquids.
• Composition and raw materials. Usually their composition is standard: propylene glycol, vegetable glycerin, nicotine, food flavors. Sometimes distilled water, alcohol are added. The idea in infusion is better mixing different properties these substances. This is especially important if you are a manufacturer and purchase a batch of raw materials for the production of liquids, as a rule, raw materials are a mixture of flavors and components, without a pronounced taste.
• Testing. an important step in the infusion of liquids is the tasting of the liquid. During the infusion, try what happens, what flavors are revealed, write down the infusion time during testing and over time you will understand when the liquid was infused as it should, and you will know the exact time required for this.
• Contact with air. Be aware that fluids can be exhaled and come into contact with air every time a container of fluids is opened. In some cases, it will change the color, and in some cases it will take away the taste.
• Maillard reaction. Chemical reaction between amino acids and sugars, changing the color of liquids. Like baking and darkening a cake, or browning pizza, darkening steaks. Some manufacturers are sure that it is the Maillard reaction that underlies the color change of liquids. We have a separate opinion on this, about it a little later.

And now let's do experiment

Without a doubt, the infusion of liquids changes their characteristics, often even changing the color. But what about the taste?

So, for some reason, you decided to buy an electronic cigarette. Perhaps they followed fashion trends. Maybe you are trying to quit smoking this way. Excellent - the device was chosen, bought. It remains the case for small - to choose a liquid. But in fact, this moment is even more important than the choice of the cigarette itself. It is the fluid that determines taste sensations you experience while inhaling the vapor.

In order not to get confused when choosing a liquid for a vape, you need to be able to choose it correctly. A beginner faces a number of questions: how to decide on a fortress? which brand to choose? what flavor to start with first? Particularly extreme beginners even care about this question: what will happen if you drink e-liquid for vaping?

Having decided on the choice of an electronic cigarette for a beginner, the next decision will be the choice of liquid for electronic cigarettes.

When choosing a liquid, you need to pay special attention to three criteria:

1. glycerin content;
2. the amount of nicotine;
3. taste.

It is believed that the higher the concentration of glycerin in the composition of the liquid for vaping, the thicker and more saturated the blown vapor will be. If there is more propylene glycol in the composition, you will not get a large cloud of vapor, but you can enjoy a rich taste.

Liquids for electronic cigarettes are both nicotine-free and with different nicotine content. If you do not want to harm your health, it is better to choose the first option.

The taste is selected solely based on your preferences. Vaping stores offer a wide range of tastes: fruit, menthol, dessert, berry. For people who want to quit smoking, tobacco-flavored e-liquids can be chosen first. Sometimes there are also very unusual tastes of liquids: the aroma of dumplings, sausage or celery will impress avid vapers who want to get new sensations.

Elements contained in the liquid

All e-liquids consist of the following components:

• glycerol;
• propylene glycol;
• flavor;
• nicotine.

The main components are glycerin and propylene glycol. They are combined in different proportions, most often 30-40% of one substance for 50-60% of another. For dilution, 10% distilled water is used.

The higher the concentration of glycerin in the composition, the greater the vapor cloud. If you have purchased an electronic cigarette with a sub-ohm vaporizer and a winder for blowing out voluminous clouds of vapor, then you should pay attention to Special attention specifically on liquids with a predominant content of glycerin.

If desired, you can mix one liquid with another, creating new combinations of flavors and achieving for yourself the optimal content of the main components. So the answer to the question of whether it is possible to mix different liquids is yes.

Why do you need nicotine in e-liquid

Nicotine is needed to satisfy the need for saturation with this substance. If you are a beginner, then do not initially buy liquid with high content nicotine (more than 18 mg). Unaccustomed to the body, nicotine poisoning can occur.

How to determine the right fortress for yourself

You can choose the strength of e-liquid for vape based on the following table:

A beginner, even if he is a heavy smoker, does not even need to try to immediately buy a strong liquid. On many devices with sub-ohm vaporizers, the strength is felt much stronger than indicated on the bottle. So you need to focus not only on the above table, but also on the type of electronic cigarette. It is always better to gradually increase the nicotine content in order to find the optimal concentration for your body.

How much fluid is required

For refilling, 10 and 30 ml bottles are usually used. Fluid consumption is influenced by factors such as the frequency and intensity of soaring, as well as the design of the device itself. On average, a 30 ml bottle is enough for 1-1.5 weeks. Beginners usually spend much less, and experienced vapers - more. All this suggests that the consumption of liquid for electronic cigarettes is individual for each person.

Brand Overview

Now that you have an idea of ​​how to choose the right e-liquid based on individual preferences, you can get more information about e-liquid brands.

Among Russian brands, the most popular are Armango6SafeLiq and Red Smokers Corsar. The last two options will not hit the wallet, but at the same time they have a rich selection of flavors of different saturation.

Chinese e-liquid brands: Vardex, Dekang, Joyetech. The latter is the world's leading brand selling e-cigarette refills. New flavors produced by this company are quickly becoming popular.

Among the premium brands it is worth noting Flower Art and Savourea. Liquids are produced in European pharmaceutical laboratories and have an incomparable taste.

Electronic cigarettes are a great alternative to traditional cigarettes during the intermediate stage before complete failure from smoking. Remember that even replacing regular cigarettes on electronic devices, you will not get rid of bad habit. Even low maintenance nicotine in liquids causes harm to health, even if less significant than regular cigarettes. Observe the measure in "soaring", thereby trying to completely get rid of the addiction.

AT Everyday life we are constantly confronted with three states of matter - liquid, gaseous and solid. We have a fairly clear idea of ​​what solids and gases are. A gas is a collection of molecules that move randomly in all directions. All molecules of a solid body maintain their mutual arrangement. They make only slight vibrations.

Features of a liquid substance

What are liquid substances? Their main feature is that, occupying an intermediate position between crystals and gases, they combine certain properties of these two states. For example, for liquids, as well as for solids, the presence of volume is characteristic. However, at the same time, liquid substances, like gases, take the shape of the vessel in which they are located. Many of us believe that they do not have their own form. However, it is not. The natural shape of any liquid is a sphere. Gravity usually prevents it from assuming this shape, so the liquid either assumes the shape of a vessel or spreads over the surface in a thin layer.

In terms of its properties, the liquid state of a substance is especially complex, due to its intermediate position. It began to be studied since the time of Archimedes (2200 years ago). However, the analysis of how the molecules of a liquid substance behave is still one of the most difficult areas of applied science. There is still no generally accepted and completely complete theory of liquids. However, we can say something about their behavior quite definitely.

Behavior of molecules in a liquid

Fluid is something that can flow. The short-range order is observed in the arrangement of its particles. This means that the location of the neighbors closest to it, with respect to any particle, is ordered. However, as it moves away from others, its position in relation to them becomes less and less ordered, and then the order disappears altogether. Liquid substances are made up of molecules that move much more freely than in solids (and even more freely in gases). For a certain time, each of them rushes first in one direction, then in the other, without moving away from its neighbors. However, a liquid molecule breaks out of the environment from time to time. She gets to a new place by moving to another place. Here again, for a certain time, it makes oscillation-like movements.

Contribution of Ya. I. Frenkel to the study of liquids

Ya. I. Frenkel, a Soviet scientist, has made great contributions to the development of a number of problems devoted to such a topic as liquid substances. Chemistry advanced greatly thanks to his discoveries. He believed that thermal motion in liquids has the following character. For a certain time, each molecule oscillates around the equilibrium position. However, it changes its place from time to time, moving abruptly to a new position, which is separated from the previous one by a distance that is approximately the size of this molecule itself. In other words, inside the liquid, the molecules move, but slowly. Some of the time they stay near certain places. Consequently, their movement is something like a mixture of movements in the gas and in the solid body. Oscillations in one place after a while are replaced by a free transition from place to place.

Liquid pressure

Some properties of liquid matter are known to us due to constant interaction with them. So, from the experience of everyday life, we know that it acts on the surface of solid bodies that come into contact with it, with certain forces. They are called powers.

For example, when opening a tap with a finger and turning on the water, we feel how it presses on the finger. And the swimmer who dived on great depth, not accidentally experiencing ear pain. It is explained by the fact that eardrum ear is affected by pressure forces. Water is a liquid substance, so it has all its properties. In order to measure the temperature of the water at the depth of the sea, very strong thermometers should be used so that they cannot be crushed by the pressure of the liquid.

This pressure is due to compression, that is, a change in the volume of the liquid. It has elasticity in relation to this change. The forces of pressure are the forces of elasticity. Therefore, if a fluid acts on bodies in contact with it, then it is compressed. Since the density of a substance increases during compression, we can assume that liquids have elasticity with respect to a change in density.

Evaporation

Continuing to consider the properties of a liquid substance, we turn to evaporation. Near its surface, as well as directly in the surface layer, forces act that ensure the very existence of this layer. They do not allow the molecules in it to leave the volume of the liquid. However, due to thermal motion, some of them develop rather high velocities, with the help of which it becomes possible to overcome these forces and leave the liquid. We call this phenomenon evaporation. It can be observed at any air temperature, however, with its increase, the intensity of evaporation increases.

Condensation

If the molecules that have left the liquid are removed from the space located near its surface, then all of it eventually evaporates. If the molecules that left it are not removed, they form steam. Once in the area near the surface of the liquid, the vapor molecules are drawn into it. This process is called condensation.

Therefore, if the molecules are not removed, the rate of evaporation decreases over time. If the vapor density further increases, a situation is reached in which the number of molecules leaving behind certain time liquid, will be equal to the number of molecules that return in the same time to it. This creates a state of dynamic equilibrium. The vapor in it is called saturated. Its pressure and density increase with increasing temperature. The higher it is, the large quantity molecules of a liquid has sufficient energy for evaporation, and the greater the density of the vapor must be in order for condensation to be equal to evaporation.

Boiling

When, in the process of heating liquid substances, a temperature is reached at which saturated vapors have the same pressure as the external environment, an equilibrium is established between saturated vapor and liquid. If the liquid imparts an additional amount of heat, the corresponding mass of liquid is immediately converted into vapor. This process is called boiling.

Boiling is the intense evaporation of a liquid. It occurs not only from the surface, but concerns its entire volume. Vapor bubbles appear inside the liquid. In order to go into vapor from a liquid, molecules need to acquire energy. It is needed to overcome the forces of attraction, due to which they are held in the liquid.

Boiling temperature

This is the one at which the equality of two pressures is observed - external and saturated vapors. It increases as pressure increases and decreases as pressure decreases. Due to the fact that the pressure in the liquid changes with the height of the column, boiling in it occurs for various levels at different temperature. Only located above the surface of the liquid in the process of boiling has certain temperature. It is determined only by external pressure. This is what we mean when we talk about the boiling point. It differs for different liquids, which is widely used in technology, in particular, in the distillation of petroleum products.

The latent heat of vaporization is the amount of heat required to convert an isothermally defined amount of liquid into steam if the external pressure is the same as the saturated vapor pressure.

Properties of liquid films

We all know how to get foam by dissolving soap in water. This is nothing but a lot of bubbles, which are limited by the thinnest film consisting of liquid. However, a separate film can also be obtained from the foaming liquid. Its properties are very interesting. These films can be very thin: their thickness in the thinnest parts does not exceed a hundred-thousandth of a millimeter. However, they are sometimes very stable, despite this. The soap film can be subjected to deformation and stretching, a jet of water can pass through it without destroying it. How to explain such stability? In order for a film to appear, it is necessary to add substances that dissolve in it to a pure liquid. But not any, but those that significantly reduce surface tension.

Liquid films in nature and technology

In technology and nature, we mainly meet not with individual films, but with foam, which is their totality. It can often be observed in streams, where small streams fall into calm water. The ability of water to foam this case associated with the presence of organic matter in it, which is secreted by the roots of plants. This is an example of how natural liquid substances foam. But what about the technology? During construction, for example, special materials are used that have a cellular structure resembling foam. They are light, cheap, strong enough, poorly conduct sound and heat. To obtain them, foaming agents are added to special solutions.

Conclusion

So, we learned which substances are liquid, found out that a liquid is an intermediate state of matter between gaseous and solid. Therefore, it has properties characteristic of both. which are widely used today in technology and industry (for example, liquid crystal displays) are a prime example of this state of matter. They combine the properties of solids and liquids. It is difficult to imagine what liquid substances science will invent in the future. However, it is clear that in this state of matter there is great potential that can be used for the benefit of mankind.

Of particular interest in the consideration of physical and chemical processes occurring in a liquid state is due to the fact that man himself consists of 90% of water, which is the most common liquid on Earth. It is in it that all life happens. important processes both in plant and animal kingdoms. Therefore, it is important for all of us to study the liquid state of matter.