Candy or life: Halloween as a reason to attract a child to science

Today, dear friends, I would like to deviate a little from serious topics, scientific research, quantum physics, neurobiology, and others. As you know, October 31st is the eve of All Saints Day or Halloween. This holiday or event, as you like, is not as common in the CIS countries as in Western Europe and overseas. I myself have never celebrated this day, because I believe that, regardless of the history of this day, now it is mostly an event for children. Dress up the costume of your favorite superhero or scary monster and go "on the hunt" for sweets. It sounds fun, especially for kids. And this is great. But before the action itself there is one important stage - preparation for Halloween. And today we will see how knowledge of science will help not only to create a frightening atmosphere to match this day, but also to teach the younger generation something. For, as we know, science surrounds us always and everywhere. And science may well be fun and entertaining. Go.



So, as I said, do not expect seriousness from today's article. She is very Friday, entertaining (I hope) and in some ways even cognitive, because you should never stop learning something. Of course, nowadays you can buy absolutely everything you need to make your Halloween party look stunning. But it's not interesting either, is it? Therefore, wear your white coats, gloves and protective masks, for the time of strange science. And remember - safety first.

')

Hellish flame of a small candle



In horror films, where some ghost appears to be the main villain, inexplicable things often happen: either the books fall by themselves, the piano starts to play, or the light of a candle turns into hellish flames. The latter is quite possible to do yourself, unless of course there are the necessary tools. To create the flame itself, we need alcohol, a tea candle (pill), a tall cylindrical glass, the diameter of which allows us to put a candle inside, and something that we can cut this glass. Ideally, you can use a glass cutter.



So, first you need to cut off the bottom of the glass, and then divide the resulting cylinder vertically in half.









Add some alcohol to the candle and light it. After that, place both halves of the glass around the candle. Shifting the halves, you will see the flame grow larger, much larger.



Why it happens? It is all about air, more precisely oxygen, which is contained in air. This gas is important not only for us, but also is the nutritional basis of any fire. No air (oxygen) - no fire. When you move the cylinder halves, you create additional oxygen access points, due to which the flame increases.





The box is actually not empty, it contains CO ₂ (carbon dioxide), in which the candles will not burn, therefore they are extinguished.



And you can play your guests at the table quite simply, if you attach a thin thread to the half cylinder, pulling which (imperceptibly, of course), you will cause an “unexpected” paranormal activity. The more such candles will be on the table, the more spectacular.



Lizun



Remember the great movie Ghostbusters (1984)? One of the secondary characters that has become quite popular is a poltergeist named Lizun - a green, glowing ghost with a big appetite and a lack of manners. Would you like to have such a friend? Not? But the children would not mind. And since we are with you for a scientific approach, a seance is not an option. Therefore, we can create something similar. For this we need: a felt-tip pen of any color to your taste (not literally), 150 ml of water, an ultraviolet lamp (I know, not everyone has it in the closet, but you can buy it at a fairly low price), ordinary office glue and a pinch sodium tetraborate.







First, pour 150 ml of water into a large container. Then take a felt-tip pen and take out its core, place it in water until it turns the color of a felt-tip pen. Now you need to turn off all the lights in the room, turn on only the ultraviolet and send it to our colored water. Now you need to add glue, the volume depends on the consistency and quantity you need (but in this case you need to increase the volume and water too). In the resulting mass, resembling dough, add literally 1/2 teaspoon of borax (sodium tetraborate). The mixture is ready, but not very much like Lizuna. To give it elasticity, you need to pour the mixture into warm boiled water. Voila, Lizun is ready. Green, elastic, glows in the dark, but does not try to eat all the supplies and litter all over the house, which is good news.



In this recipe, the most unusual is the fact that a conventional felt-tip pen and ultraviolet can create a glowing effect in the dark. But how and why? The answer in one word is fluorescence. The point is that in the marker there is a certain chemical compound that causes this effect when exposed to ultraviolet radiation. If the pen is yellow, then it is rhodamine-6G. If you do not go into details of how the process of fluorescence, you can describe it quite simply. Fluorescent material absorbs high-energy light waves, and emits lower-energy light waves. Take a yellow marker and draw something on a white sheet. It looks bright, but if you bring it to sunlight, your drawing becomes even brighter. However, because of the sun, you cannot fully observe the effect of fluorescence. Therefore, it is best seen in the dark, when external light radiation does not interfere.







The pen and ultraviolet light can also be used for festive decor. To do this, simply dissolve the pen in the water and put flowers into it (preferably white) at night, then expose them to ultraviolet light, and the flowers will become fluorescent.



Extraterrestrial "guests"



Remember how in the old black and white films something flew from space and it looked like an ordinary stone, but smoking? And I do not remember. :) Well. Let's do this.







They say that there is no smoke without fire. This is true, but is it possible to say otherwise - there is no smoke without ice? Of course you can, if we are talking about dry ice, which is the main ingredient for the preparation of a comet.



For this we need glucose (substance, not a singer), bleach, a little dry ice (obviously), water and sand.



To begin with, pour a glass of water (approximately 250 ml) into a convenient vessel and add sand (1.5-2 tbsp). Stir until we get a homogeneous mixture without lumps. Next, add glucose (as much sand - as much glucose), mix. Now we introduce a little bleach (about 1.5 tablespoons). And now add the most important ingredient - a glass of crushed dry ice and mix thoroughly. The important point is that all this should be mixed not just in a pot, but put into it a pre-dense crumpled (for a beautiful relief) package. Now you need to get the mixture in the package and wrap it so that there remains a small hole for the gases to exit. When the substance hardens, you can deploy the package. In no case do not take the mixture with your bare hands. The result of your needlework will be a stone, but not simple, but smoking. Decorate the table for them and tell the guests that you found it in the courtyard after a strange loud bang.





A slightly different recipe is offered by NASA in its video tutorial.



What is so special about dry ice? And why dry? This is ice, and ice consists of water, and water is wet. Is logical. I would even say "flawless logic." Okay, okay, Spock would say that. But more to the point.



Firstly, it is worthwhile to disappoint everyone who believed that this substance is just a strange type of ice. This is not true. The word "ice" in the name is present solely because of the appearance of ordinary ice. Dry ice is solid carbon dioxide. In other words, it is solidified CO ₂ . His main feature is that he does not like to stand in line. Normal ice is a solid form of water (H ₂ O). Ice melts, we get water - the liquid form of H ₂ O, the water evaporates - gaseous. Dry ice passes the liquid state and goes directly from solid to gaseous. An important feature of dry ice is its temperature, which at normal pressure is about -79 ° C, which is why it is very dangerous to take it with bare hands.

PS A huge request to always observe safety precautions and teach this to your child. Getting injuries during the experiments can not be called instructive and enjoyable experience neither for you nor for the child.

Epilogue



Yes, the article is small, Friday to the bone, but I really hope that it was interesting for you and for your children. After all, it is necessary to inculcate the love of science from an early age. And how best to do it? Of course in the form of a game. You do not need to be a psychologist to understand how nice and important it is for a child and parents to do something together. Let it be a stupid, strange and even in some sense useless activity, but you will do it together.



Science should not frighten children with its complexity, because even the most complex phenomena can be explained very lucidly and cheerfully. Even if you do not celebrate Halloween, as I, for example, the above experiments, let's call them so, you can carry out without cause. More precisely, he is always there - a cheerful knowledge of the world around him along with your child. By the way, once in a store I saw a grandmother with a grandson, to whom she repeated 100 times “don't go anywhere”, “stand still”, “don't touch anything”. I understand, she is afraid that the child may get lost or hurt. But so severely restrict the freedom of man, and the child is a small man, it is impossible. How will he know the world standing still? In any case, love children (as if sometimes they do not enrage you), love each other, have a nice weekend and you are frightening Halloween.





PS And do not forget to share personal experience. What scientific experiments have you done with your children or can your parents with you? Here is my mother explaining the diffusion process to my elder brother on the example of how potassium permanganate dissolves in water. Returning from school, I saw a glass and thought it was a compotiate. (smiley) In general, it was not worth taking such a big sip. So I got acquainted with chemistry in elementary grades. Clarification: the brother knew that it was not a compote, but he did not say anything. I took revenge on him with salty tea.



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