Author Igor Bukker
14.05.2021 15:21
Health
Mineral water is an attribute of a healthy lifestyle and an effective medicine. It is used to fill baths, pour over it, and is used for rinsing and inhalation, but most often it is drunk.
The guest of the next episode of the Point of View program was mineral water expert Mikhail Olkhov , business development director of STELMAS-D LLC.
— How can mineral water help the body?
— Water plays a decisive role in human life. It is enough to remember at least what the main aspects of a healthy lifestyle of a person generally consist of.
Naturally, it all depends on what is most important to us, without which we cannot exist in principle.
- The first is oxygen. We cannot stop breathing for more than 3 minutes.
- The second is water. We can last about seven days without water at most.
- Third is nutrition. A person can survive 40 days without food.
- The fourth is movement. Because even if the first three aspects are generally present in our life, but completely immobilize us, irreversible changes will gradually begin in the body.
- The fifth aspect is the absence or presence of bad habits, because here we ourselves decide how to treat our body: with care or not.
- The sixth aspect is heredity. Here we can no longer influence anything at all; what is given is given. But if we know that there are some chronic diseases in our family, this is a very important wake-up call for us so that we at least observe the first five aspects.
Boiling water
- Participant: Yaroslavtsev Maxim Alexandrovich
- Head: Trubenko Faina Ivanovna
Experiment 1. A.V. Peryshkin. Physics 8, § 18.
| Safety precautions | Safety rules when working with alcohol lamps and glassware. | ||
| Purpose of the experiment | Observe the process of boiling water and describe the main phenomena that accompany the process of boiling water. | ||
| Hypothesis: | The boiling process is accompanied by a number of amazing phenomena | ||
| Equipment: | Photo | ||
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| Description of the experience | Experimental results | Explanation | |
| We fix a flask with water in the tripod leg, and place an alcohol lamp underneath. We light the alcohol lamp and observe the processes occurring in the flask. | 1. There is abundant evaporation from the surface of the liquid, and fog forms above the neck of the flask. | 1. The steam is invisible, but when it enters a cold environment (outside air), the steam condenses and fog is formed. | |
| 2. Bubbles form and begin to grow on the inner surface of the walls. | 2. Bubbles contain air dissolved in water and water vapor, which is formed due to the evaporation of water inside the bubbles. | ||
| 3. The bubbles increase in size, break away from the walls of the flask, rise up and disappear. | 3. Steam condensation occurs in cold, unheated layers of water. | ||
| 4. There is a noise preceding the boiling of water. | 4. The noise is caused by the alternate decrease and increase in size of bubbles, the water gradually warms up completely. | ||
| 5. Bubbles float to the surface, burst, you can hear the water gurgling, boiling. | 5. Bubbles float to the surface under the influence of Archimedean force, saturated steam from the bubbles is released into the atmosphere. | ||
Experiment 2. Boiling of water at reduced pressure
The liquid will boil if the saturated vapor pressure in the bubbles is greater than the sum of the hydrostatic pressure of the liquid and atmospheric pressure:
rnas. n. > ρgh + ratm.
From this expression it follows that by changing the external pressure above water, you can change the boiling point of water: when the external pressure decreases, the boiling point decreases, and when the pressure increases, it increases. Let us prove this conclusion experimentally.
| Safety precautions | Safety rules when working with glassware | ||
| Purpose of the experiment | Observe the process of water boiling under low pressure conditions | ||
| Hypothesis: | When the external pressure decreases, the boiling point decreases | ||
| Experience 2 | |||
| Equipment: | Photo | ||
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| Description of the experience | Experimental results | Explanation | |
| A) Measure the initial temperature in the flask. | The initial water temperature is 30 °C. | When we pump air out of the flask, the pressure above the liquid decreases, the process of bubble growth begins at lower pressure, which affects the boiling point. | |
| b) We fix the flask with water in the tripod leg and close it with a rubber stopper with a glass tube. Connect the flask to the pump using a rubber hose. We pump out the air from the flask. | Bubbles form in the water, they rise to the surface of the water, burst, and the water boils. | ||
| c) Measure the temperature of the water after boiling. | The final water temperature is 29 °C (the decrease in temperature is caused by heat transfer from water to the environment). | ||
Experiment 3. Problem No. 862 (snow replaced by cold water)
(A.E. Maron, E.A. Maron, S.V. Pozoisky. Collection of questions and problems Physics 7-9 for the textbook by A.V. Peryshkin)
| Equipment: | Photo | ||
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| Description of the experience | Experimental results | Explanation | |
| Bring the water to a boil in the flask. Remove the alcohol lamp and close the flask tightly with a rubber stopper. We turn the flask with water over and secure it securely in the tripod leg. Pour cold water over the top of the flask | Air bubbles form in the water and the water boils. | Cold water cools the hot air above the water in the flask, its pressure above the liquid decreases. Water boils at temperatures below 100°C. | |
| Application of the phenomenon under consideration in practice. |
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| Natural phenomena | Geysers are one of the most amazing natural phenomena; they are periodically gushing sources of hot water with steam. |
| Interesting facts in the phenomenon under consideration | An interesting problem from problem book 861 (experiment with a syringe). It can be demonstrated on L-micro equipment. Observation of the boiling of alcohol: a test tube with alcohol is placed in a vessel with boiling water, the boiling point of the water is recorded, the pressure above the alcohol is increased using a syringe, the graph shows an increase in the boiling point of the alcohol (in the corner of the graph t boiling point at normal and elevated pressures). |
| Boiling distilled water. Distilled water is purified H2O water that contains virtually no impurities. Pour distilled water into a clean flask and begin heating over low heat. Using an electronic thermometer, we measure the temperature of the steam above the water (Fig. 1). We see that at a temperature of 100 °C water does not boil. We remove the alcohol lamp and throw pieces of chalk into the superheated water (Fig. 2), bubbles immediately form on its surface. We see rapid boiling of water (Fig. 3). rice. 1 Fig.2 Fig.3 | |
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Video link https://cloud.mail.ru/public/4k82/e7MeqkpeB (Mail.Ru Cloud)
The video contains all the fragments:
- Boiling water;
- Boiling under reduced pressure (using a pump and cold water);
- Boiling distilled water.
Topic: Thermal phenomena
Emergency situations associated with changes in tap water temperature
There are a number of basic and common problems that are directly related to exceeding the temperature of cold water in water supply systems.
Such problems arise regardless of the time of year and typical features of the water pipeline.
A slight warming of water is characterized by an increase in temperature indicators of only 6-10°C, but more pronounced fluctuations occur quite often not only in conditions of autonomous water supply to the private residential sector.
If warming of cold water coming from the tap occurs in a multi-apartment residential building with a centralized hot water supply, then we can assume the problem of mixing hot and cold water media under conditions of unequal pressure inside the pipelines. As a rule, the main reason for such mixing is a malfunction of the standard mixer installed on the distribution riser.
Somewhat less often, the mixing of aqueous media is the result of gross errors made in the process of performing basic sanitary and technical work in the technical underground, which causes hot water to be thrown into the cold main.
It is important to remember that any problems accompanied by even short-term injection of hot water into the cold water supply system must be eliminated as soon as possible. Otherwise, expensive automatic washing machines and dishwashing equipment, as well as many other household appliances operating using a cold water supply system, will fail.
To prevent warming of cold water in the tap when operating any electric water heating devices, it is necessary to promptly cut off the hot water supply circuit while using the heating element, as well as cut off boiler devices in conditions of water intake from the common riser.
The presence of two open circuits most often causes mixing of hot and cold environments, and also provokes the occurrence of powerful water hammer, and, as a result, breakdown of plumbing.
The use of flow-type gas water heating devices for hot water supply is based on the operation of the unit without adding cold water, and the temperature indicators of the water supplied to the tap should be set only by changing the heating level on the equipment itself. Otherwise, overheating and subsequent shutdown of the burners in emergency mode occurs.
GOST and SanPin set the standard temperature in the apartment. But there are certain factors that influence its change. Let's talk about them in more detail.
Is it worth installing an individual heat meter in an apartment? We’ll figure it out further.
Red up! Green down! Beautiful experience with water
Hello everyone! The ShkolaLa blog invites you to our “Home Laboratory”. Come in, don’t be shy, settle in) Get ready, it will be interesting!
Today our little researchers Artyom and Alexandra will conduct another experiment in the field of physics. Namely, experience with hot and cold water.
The guys needed the most common tools and equipment. This is some kind of large container, with glass walls, so that you can better see what is happening. A couple of small jars or some kind of vials, you can also use baby food jars or penicillin vials. Dyes, we have them left over from other experiments. You can also use food coloring, watercolor paint, gouache or ink.
Well, you will also need water. In a large container at room temperature, and in jars it is hot and almost icy.
Let's first see what they come up with, and then try to find an explanation for what we saw. Do you agree?
Go!
So what do you think? I think it turned out very beautifully.
But why did the hot water rise upward in a red stream, and the icy green snake quietly fall to the bottom? Alexandra suggested that this is all happening because hot water is simply easier. That is, if you weigh a liter of cold and a liter of hot water, the hot water will weigh less. However, physicists are not sure about this.
I'll tell you more. Physicists believe that hot water is heavier than cold water. The great scientist Albert Einstein, whom I already told you about, determined the relationship between energy and matter. He derived a formula that connects body mass and its energy. The formula looks like this.
Dear little schoolchildren, if you don’t understand anything right now, don’t despair. When you grow up, you will begin physics lessons and then everything will become clear. Now let’s try to figure it out a little bit, without going too deep into the scientific jungle.
From the above formula it becomes clear that the greater the energy of a body, the greater its mass. How can we increase the amount of energy? The simplest ways are to properly accelerate or warm up the body. It turns out that heated water will actually weigh more! But in order for the most accurate and sensitive measuring instruments to feel the increase in mass, at least 1 ton of water will be required.
And on our scale, this increase in mass is so small that it cannot in any way affect the course of the experiment. Well, what's the matter then?
It's all about density! Any substance, any body has it. You will again learn more about what this is from your physics teacher. Let me remind you that those substances whose density is greater than the density of water will drown. And those whose density is less will float on the surface.
And water has density. And it depends on the temperature. The colder the water, the higher the density and vice versa.
Now look what happened.
We poured water at room temperature, approximately 20 degrees, into a glass container. At this temperature, the density of water will be 998.23 kg/m3.
The cold water temperature was approximately 4 degrees. Density - 1000 kg/m3. That's why she went down.
Well, the hot water had a temperature of approximately 60 degrees. And a density of 983.24. And so she rose up.
Phew, it seems like we figured it out) What an interesting science - physics!
And sometimes physical experiments look like real magic. Look, for example, at the article about experiments with balloons or “magic drops”.
Well, we say goodbye to you, only to meet again in our “Home Laboratory”. Don't miss new experiences and experiments! Subscribe to blog news!
And join our VKontakte group, we’ll communicate there too!
Always yours Artyom, Alexandra and Evgeniya Klimkovich!
Temperature according to GOST
The qualitative composition of all water used for household and drinking needs must fully comply with the current State Standard, and for production purposes it is regulated by technological requirements.
The temperature regime of cold water in the GOCT tap is not regulated, but you need to remember that these indicators directly depend on the time of year.
This feature is associated with the temperature of the water at the source of water intake, as well as the temperature indicators of the soil at the level of the water pipeline.
In the main water supply, the water temperature can even be negative, since under conditions of high pressure inside the system, the process of freezing the liquid is noticeably slowed down.
It should be noted that in residential buildings and industrial facilities, where it is not possible to fully meet the needs of all consumers through sources of drinking water supply, the presence of technical and economic feasibility, as well as approvals from the SES, makes it possible to supply non-drinking water to premises with some basic plumbing fixtures.
Despite the fact that temperature standards for cold tap water are not provided for by regulations, local recommendations of service organizations often set parameters within 4-20 ° C.
In winter, some apartments can be extremely hot, while others, on the contrary, are very fresh. The temperature standard in the apartment during the heating season must be regulated by the management company.
Kitchen flooring options are presented in this review.
If you have started a renovation, you cannot do without calculating the square meters of the room. You will learn how to correctly calculate the square footage of a room in this article.
