Participating in simple but spectacular egg experiments will delight children and show them that science can be fun and exciting. All these tricks are easy to do at home, and it will not require significant costs.
Submarine
The salt water experiment will help children understand how you can change the properties of a liquid just by adding salt to it.
For experience you will need:
- raw eggs (fresh);
- 3 half-liter jars without stickers;
- salt.
Pour water into two jars and invite the child to dip an egg into each of them - they will immediately fall to the bottom. Then add a few large spoons of salt to one container and mix gently: the “experimental” will float to the surface. In an empty third jar, put another egg and alternately pour fresh and salt water into it so that it hangs in the middle.
shell dissolution
This experiment will show what happens if you put an egg in vinegar. To carry it out you will need:
- a raw egg;
- table vinegar;
- wide glass or jar.
Dip the egg in a glass of vinegar and watch it with your child for a few minutes. At first, as in the case of fresh water, it will sink, but the acidic solution will soon react with the calcium compound that makes up the shell. Bubbles of carbon dioxide will begin to form on its surface (the rate of their appearance depends on the concentration of vinegar). In this form, the glass must be left for several hours or even days, until the shell is completely dissolved. The resulting “ball”, covered with a thin film, will bounce off the table like rubber. It can be carefully crushed in your hands or shined with a flashlight - the yolk on the cords will be clearly visible.
The experiment is time consuming, so take a few eggs at once in case one breaks.
About the benefits of toothpaste
There is another version of the previous experience with eggshells and vinegar, proving the need for regular brushing. The difference in the experiment is that before immersing in the acid solution, one half of the experimental product must be generously smeared with any toothpaste. Only the shell on the raw half will dissolve.
Super Strength
This trick has a simple explanation in terms of physics, but for preschoolers it will be a real miracle. It will take a couple of dozen eggs, evenly laid in two factory forms. On top of every ten you need to put a plank (small cutting boards made of plastic or wood will do) and boldly stand on them with your feet - this design can withstand even an adult. For greater entertainment and acuity, you can do without planks.
Focus with a bottle
For the classic bottle experience, you will need the following kit:
- hard-boiled and peeled egg;
- matches;
- a small strip of paper;
- a bottle with a wide neck (an egg in a vertical position should close it without slipping inside).
Make sure with your child that the egg cannot be pushed into the vessel with the help of hands. Then set fire to the paper and throw it into the bottle. After that, you need to close the neck, inserting an egg into it with a sharp end, and wait what happens. Gradually, it will begin to be drawn into the bottle, taking an elongated shape right before our eyes, until it falls to the bottom. The reverse process will help to take it out: you need to turn the bottle over and heat its bottom from the outside.
Fire can be replaced with boiling water - just pour a little into the bottle and shake slightly to warm the bottom, then pour it out and continue the experiment.
Silver ball
Spectacular trick for children, which is able to decorate the program of the holiday. You will need:
- egg (raw or boiled);
- convenient tongs (for example, for spaghetti);
- a candle or other source of open fire;
- a glass of plain water.
In front of the audience, hold the egg over the fire with tongs until it is covered with a black coating (a few seconds will suffice). Let the children admire the result for a while, then dip the charred egg into the water. It will look like it was cast from pure silver! Of course, until you get it out of the water.
Spectacular fall
The trick with an egg falling into a glass is always a hit with the kids. For him, you need to prepare:
- a raw egg;
- a glass of water;
- a small piece of cardboard;
- toilet paper roll or other suitable ring.
Build a structure: put cardboard on a glass of water, put a sleeve on top (so that it is above the center of the glass), and place the main ingredient itself on top. With a light but sharp movement, knock the cardboard out from under the sleeve, these auxiliary parts of the building will scatter, and the egg will fall right into the glass.
As a bonus, teach the kids to tell if they have a raw or boiled egg. All that is needed for this is to try to spin it like a top. Raw will not make even a couple of revolutions, and cool will rotate very quickly.
People who at least sometimes go into the kitchen to not only eat, but also cook something, notice useful little things over time. For example, that eggs do not float during cooking, but lie on the bottom. Therefore, the vague suspicions that arise when a raw egg floats in water are not unfounded.
What is there inside?
The difficulties of determining the freshness of such a product when buying are obvious. Especially in supermarkets, where eggs are often sold in closed, opaque packaging. But everything becomes clear when we bring them home and start cooking. If at the same time you have to break them, then the following signs should alert you:
- The smell of hydrogen sulfide.
- Opaque white.
- When broken into a pan or bowl, the yolk immediately spreads.
But how do you test the freshness of an egg without breaking it? Just immerse in water. If the egg floats in the water, it is spoiled or stale.
Why does a spoiled egg float?
Contrary to popular belief, an egg is not hermetic at all. The shell has pores so that the chick can breathe. But in addition to oxygen, microorganisms also penetrate through them. As a result of the vital activity of some of them, putrefactive processes develop and gases are released. If an egg floats in water, it means that a lot of gases have accumulated in it, which are lighter than water.
By the way, even if there are no harmful microorganisms inside that cause rotting and an unpleasant odor, the old egg will still float. Air gradually accumulates between the protein and shell membranes on the blunt side. For the same reason, a stale egg is very light.
By the way, this is why it is recommended to store eggs with the blunt end up so that the yolk does not come into contact with the air chamber. And it is better not to put them in a compartment in the refrigerator door, as its frequent opening leads to the fact that they deteriorate faster.
If the egg does not fully float
When, when immersed in water, the egg immediately goes to the bottom and takes a horizontal position, then we have a very fresh product. But over time, the chemical processes occurring inside change the consistency of the protein and yolk, making them more liquid. Therefore, if the egg floats in the water with a blunt end up, then it is about a week old. So, you can still eat it. If it takes a vertical position, then it is about 2-3 weeks old. An egg that is more than a month old floats completely and cannot be eaten.
deceptive salt
Knowledgeable people add a little salt when boiling eggs so that accidentally broken eggs do not leak out. Therefore, it should be noted that if you first added salt to the water, then the correct definition of freshness will be in question. The fact is that salt increases. If an egg floats in water that has previously been salted, this does not necessarily mean that it is stale. But if it lies horizontally even in salt water, then there can be no fresh product.
How to determine the quality of eggs in the store
So that it does not happen that all three dozen eggs bought suddenly surface, you should try to determine their freshness when buying.
- Look It must be borne in mind that the class of the product must be indicated on the packaging. There are diet eggs that are stored for no more than 8 days, and there are canteen eggs (blue print), which we most often buy. Their maximum shelf life is a month. There is also a class of long-term ones. They can be kept in the refrigerator for about six months, but these are rarely found in stores.
- Examine the surface. The shell should be matte and slightly rough. It is smooth and shiny only in stale eggs.
- Weigh the egg in your hand. If it is old, it will be very light in weight.
- Shake the egg. When it is fresh, the yolk does not move inside. This means that you will not feel that something is hanging in the shell, and you will not hear any sounds when shaking.
Well, now we have figured out what's what, and realized that if the egg floats completely in the water, then it is stale, or even rotten. However, a boiled egg may float up, mistakenly placed next to raw ones, but such confusion rarely occurs. Therefore, it is better not to save on health and throw away a stale product.
The kitchen is a great place to experiment.
Chuda and I recently conducted two simple but nonetheless interesting experiments in physics.
We invite you to experiment with your children!
All that is needed for these experiments is -
- two raw eggs
- one boiled egg
- two cans of water
FIRST EXPERIENCE-
We take two eggs, one of them raw and the other boiled, and try to determine which is which without breaking them.
For us adults, this is not difficult, and every housewife will determine this with ease. But it will be very interesting for a child to twist and observe that they are spinning in completely different ways.
Everything is explained very simply! In a boiled egg, the center of gravity is constant, so it spins. And a raw egg has a liquid mass inside, and the center shifts all the time, being a brake, so a raw egg spins with difficulty.
SECOND EXPERIENCE -
We NEED - two raw eggs and two cans of water, a few tablespoons of salt.
Let's try to find out what What will happen to an egg if you put it in a jar of water?
First, put the egg in a jar of clean water - the egg sank to the bottom.
Add salt to the second jar, and release the egg into this jar - the egg remains floating on the surface of the water.
Again, the explanation is very simple. —
Salt increases the density of water! It's all about the density of the water. The higher it is, the more difficult it is to drown in it. That is why it is much easier to swim in a salty sea than in a freshwater river. Salt water helps to stay on the surface. For example, in the Dead Sea, which has a very strong concentration of salt, a person can safely lie on the surface of the water without fear of drowning.
We participate with our experience in an exciting and educational
It is necessary to develop the baby from birth. To do this, it is not necessary to strictly follow the instructions on psychology, to study a bunch of monotonous literature. It is enough to spend more time with the child, show him tricks, explain incomprehensible phenomena, make toys together.
Such joint activities make the child more developed and raise the authority of the adult. Become a magician and magician for your child, give him joyful moments of communication, develop in him an interest in the surrounding reality and show by example the importance of the necessary regular procedures, conduct joint experiments and experiments with available products.
Boiled or raw?
Even simple cooking in the kitchen can benefit your little one. To do this, it is enough to use those products that are always at hand. For example, experiment with a chicken egg at home. Such events will help to understand the intricacies and complexities of individual things and objects, as well as answer a number of difficult questions.
First, teach your child to distinguish a boiled egg from a raw one. In appearance, they are exactly the same, so at first glance it is impossible to make the right choice.
To do this, you need to spin the eggs and see how they behave. The boiled will immediately begin to spin, and the raw will practically stand still. Such experiments with the egg will explain to the child that everything depends on the internal state.
A boiled egg has a dense mass, while a raw one is liquid. The liquid will slow down the process, so the raw egg will not spin.
Experiments with eggs and vinegar
To explain to a child why you need to brush your teeth daily, it is enough to conduct a simple experiment. Take an ordinary chicken egg and spread one half with the toothpaste that the baby uses. Leave the other half untouched.
Pour a solution of vinegar (9%) into a jar and place the prepared egg in it. After half an hour, show the baby what happened. The half that was smeared with toothpaste will remain the same, and the second, unprotected, will become thin and change color.
Such an example will clearly show the importance and usefulness of toothpaste, which will protect the teeth and preserve their color.
Experiences and experiments are perceived and assimilated by the child faster than reading literature. They are interesting to watch, and the results will be remembered.
pop up egg
The process of immersing an ordinary chicken egg in a solution of vinegar will bring a lot of pleasant experiences to the child. First, it will sink and settle at the bottom, then it will gradually begin to fill with a mass of bubbles. As a result of the reaction of acid with calcium, which is part of the shell, carbon dioxide is formed.
These bubbles will cause the egg to rise to the surface. As soon as the bubbles run out, the egg will again sink to the bottom and begin to gain a new portion of gases, which will again push it up.
Bubble will continue until the shell is depleted and gives up all the calcium for the reaction. The accumulation of bubbles will attract the attention of the baby, and your comments will help him understand what is happening.
If the egg is left in the solution longer, then you can get an excellent rubber ball. The egg pulled out after a while will become soft and pliable. You can throw it on a plate and it will bounce like a ball.
The child will definitely like the experiments with the egg and he will ask to repeat them, or maybe he will learn to show them himself.
Tricks with an egg
With an ordinary chicken egg, you can show your child many interesting things and thereby explain incomprehensible phenomena. For example, why is it easier to learn to swim in salt water? If you explain it in words, then it will not give anything, but to show it visually is another matter.
Take three cans. Place ordinary water in one of them, and salt water in the other. Have your child dip an egg into it and see what happens together. will push the egg to the surface, and in ordinary water it will be at the bottom. This is because salt water will be heavier than a raw egg and will be able to lift it.
Now take an empty jar and place the egg in it. Alternately pour in salt and plain water. The child will be interested in watching what is happening.
The egg will change its location. With an excess of salt water, it will float, and with its shortage, it will sink to the bottom. When the water concentration is balanced, the egg will take a middle position. It will be between the bottom and the surface.
If you do not immediately reveal the secret, then you can carry out such a demonstration in the form of a trick, forcing the egg to change position. Experiments with water and eggs are very simple and do not require special tools and financial costs. And the kids are watching with interest.
Egg in a bottle
The experience with an egg and a bottle will surprise not only the baby, but also the adult. Boil a chicken egg, let it cool and peel it from the shell. Take any container with a neck, such as a bottle. The neck should not be very narrow, but narrower than the diameter of the egg. For the experiment you will need matches.
- Stage one. Take the egg and put it on the neck, let the child try to stick it inside the vessel. This is impossible.
- Stage two. Take matches, light them and throw them inside the bottle. From above, put the egg on the neck with a sharp end, blocking the access of air.
- Stage three. Gradually, the process of sucking the egg into the vessel will begin. This interesting experiment will demonstrate the properties of air by changing the pressure inside and outside.
The experiment with the egg and the bottle can also be done in reverse order - try to get the egg back.
Turn the vessel upside down and start heating the bottom. Gradually, the egg in the bottle will begin to move in the opposite direction.
This experiment can also be carried out with a raw egg. To do this, it will be necessary to soften the shell in acetic acid.
you can pre-lubricate the neck of the bottle with oil;
to soften the shell, it is necessary to keep the egg in acid for at least a day;
close the neck with an egg as soon as the matches are thrown;
the neck should not be wide and too narrow (no more than ½ of the diameter of the egg itself).
"Vanka-vstanka" from an egg
Their eggs can make a wonderful tumbler. A naughty egg will definitely be remembered by the baby if you allow him to take part in the manufacturing process.
Necessary materials - a candle, weights in the form of nuts, metal trifles and the egg itself. The cooking process will consist of several stages.
1. Getting started, you need to get rid of the liquid inside the egg. To do this, make a small hole from the sharp end and pour the contents.
2. Then rinse the egg inside and leave to dry. When it dries, put the prepared “load” on the bottom and drip it with paraffin from a burning candle.
3. After hardening - test the egg. Check the strength of the fastening so that the load inside does not dangle. The egg must constantly return to one position, with a load on the bottom.
4. Now it remains to decorate the egg and close the hole.
You can make a toy in the form of a muzzle and glue a hat on top of the hole, thereby closing it. Let your child decorate the egg themselves. Perhaps he will suggest more interesting ways and options.
Conclusion
Spend more time with your child. His constant questions indicate that he is trying to quickly learn the world and understand all the intricacies. Help him with advice, entertaining games. Make toys together and explain incomprehensible things.
Hello dear friends! You've probably noticed that when you put your eggs in cold, unsalted water, some will float. Many thought about how to check them for freshness without tasting them. It doesn't always smell bad. Most often, you realize that it is rotten, only by preparing it. How to determine the freshness of a product? If an egg floats in cold water, what does it mean? I will tell you about this today.
For testing we need:
- Deep saucer, preferably transparent.
- Cold water.
- Eggs.
This method makes it easy to determine whether eggs can be eaten or better thrown away. Our grandmothers also used it.
- We put the bowl on a flat countertop, fill it with water, almost to the brim.
- Place the egg carefully in the water so as not to break it on the bottom. It either sinks or floats.
- Those that floated to the top should be thrown away. They have deteriorated. If a raw egg floats in water, it is not fresh. This rule applies only to pure water. Everything floats in salt water, due to the increase in the density of water. For the same reason, protein does not come out of a cracked shell during cooking. Salty liquid squeezes him.
- Drowned testicles, but standing upside down, indicate the end of the shelf life. You can still eat them, they will not bring harm. From the expiration date on the box, you can eat them for another three weeks. But be sure to test this method for freshness.
- Those that drowned and lie on their side at the bottom are the freshest. They can be eaten right away or stored in the refrigerator. The optimum temperature for storing the product is +4 degrees.
With eggs, water and salt, children's experiments are carried out to explain to the child the physical properties of water. This knowledge is applied, as you noticed, to determine the freshness of the product. https://www.youtube.com/watch?v=2uEH23Vn6_U
Why do raw eggs float?
Under the shell there is an under-shell film, moisture and air pass through it, but protein does not pass through. At the blunt end of the egg oval, the shell peels off to form an air sac. Over time, some moisture and carbon dioxide evaporate from the product, so the contents are compressed and some of the air under the shell increases. The longer the egg lies, the more air accumulates in it.
This transformation causes non-fresh eggs to float.
An unpleasant odor is formed when the protein decomposes. Under the action of microorganisms, hydrogen sulfide gas is released. It gives off a rotten egg smell. Eating rotten eggs can lead to nausea, vomiting, and diarrhea. Signs of poisoning will appear in the period from 6 to 72 hours after eating them.
Why do boiled eggs float on the surface
All boiled eggs lie at the bottom of the bowl and only one floats for some reason. What is the reason? I think many of you have experienced the phenomenon of hard-boiled popping in cold water. There is no mystery here. As mentioned above, the longer it is stored, the more air is formed in it. When cooked, this air does not go anywhere, but is collected in one place under the shell. Most often from his blunt side. You can break up and make sure the air bag in the swimmer is bigger than the rest. This indicates not the first freshness of the product. It was stored for a long time and the protein began to evaporate.
Quail eggs
Quail eggs are much healthier than chicken eggs, although they are much smaller in size. You can buy them in supermarkets, but will they be fresh? How to check it now I will tell. To check the freshness of such a product, you need to break it into a plate. Fresh protein is thick, if it is liquid, watery, then the egg is bad. The yolk of a hard-boiled egg is bright yellow when cut. If it is pale yellow, then it has already lost its nutritional qualities. The weight of a good quail egg is from 10 to 12 grams. If the testicle seemed very light to you, it means that it has already begun to dry out.
Unlike a chicken egg, a quail egg does not go rotten due to the content of lysozyme, an antibacterial substance, in it. Therefore, when the expiration date has expired, it tends to dry out. The shell of a real high-quality testicle should be camouflage. If it is white or soft, then such a product is not of high quality. You can also tell about freshness by the location of the yolk. Smashed it on a plate.
The yolk should be almost in the middle of the protein, if it is closer to the edge, then the egg is not the first freshness. Friends, I think you have learned useful and interesting facts for yourself and put them into practice. On that I say goodbye to you until we meet again on the pages of our blog. Subscribe to news, put classes, share information with friends on social networks. Goodbye.
