Chemistry is the science of matter and its interactions, and it’s all around us. From the food we eat to the air we breathe, chemistry plays a crucial role in our daily lives. Yet, despite its omnipresence, many of us remain fascinated by the mysterious and intriguing world of chemistry. In this blog post, we’ll explore ten fascinating stories that showcase the wonders of chemistry, from everyday phenomena to groundbreaking discoveries.
1. The Mystery of the Drunken Fruit: How Fruits Can Help You Sober Up
Ever wondered why fruits like lemons and limes are effective at curing a hangover? It’s all thanks to their organic acids, such as citric acid and tartaric acid. These acids can react with the alcohol in your bloodstream, forming harmless esters that help break down the alcohol and alleviate hangover symptoms.
2. The Fire That Defied Extinguishing: Why Magnesium Can Ignite in Carbon Dioxide
Imagine a fire that won’t extinguish with water or even carbon dioxide! This is the case with magnesium, a highly reactive metal. When exposed to air or water, magnesium reacts vigorously, producing heat and light. This property makes it particularly dangerous, as it can continue to burn even when surrounded by fire extinguishing agents.
3. The Laughter Gas: The Science Behind the “Laughing Gas”
Have you ever heard of the “laughing gas”? It’s a gas called nitrous oxide (N2O) that can induce a feeling of euphoria and laughter. In 1800, British chemist Humphry Davy discovered this gas while experimenting with nitrogen compounds. He accidentally inhaled it and experienced a sudden outburst of laughter, leading to the discovery of nitrous oxide’s properties.
4. The Electric Light Bulb Without Electricity: The Chemistry Behind a Light Show
How can a light bulb produce light without electricity? The answer lies in the reaction between magnesium and concentrated sulfuric acid. This reaction generates heat and light, making it possible to light up a bulb without any electrical power.
5. The Floating Egg: The Science Behind an Egg’s Submersion in Acid
Have you ever tried floating an egg in vinegar? This experiment demonstrates the reaction between calcium carbonate (CaCO3) in the eggshell and acetic acid (CH3COOH) in vinegar. The resulting carbon dioxide gas forms bubbles on the eggshell, creating a temporary buoyancy that allows the egg to float.
6. The Magic Eraser: How to Remove Ink Stains with Chemistry
Need to erase a mistake on a document? Look no further than “magic eraser” solutions, which combine substances like oxalic acid and hydrogen peroxide to break down ink molecules and remove them from paper.
7. The Secret of the Exquisite Sword: The Science Behind the “Magic Sword”
In ancient China, legendary swords like the “Gongcheng” and “Mojian” were known for their exceptional sharpness. Today, we know that the secret to these swords lies in the presence of elements like tungsten and molybdenum, which enhance the strength and durability of steel.
8. The Chemical workings of the Stomach: How the Stomach Protects Itself
The stomach is a powerful digestive organ, but it needs to protect itself from the harsh acids and enzymes it produces. The stomach lining secretes a layer of mucus and contains cells that regenerate rapidly, preventing the stomach from digesting itself.
9. The Unburnable Handkerchief: The Science Behind Fire Safety
Ever seen a handkerchief burn without being damaged? It’s all thanks to the presence of water in the experiment. The water vaporizes, absorbing heat and preventing the handkerchief from reaching its ignition temperature.
10. The “Sweating” Wall: The Chemistry Behind Freshly Painted Walls
Have you ever noticed water droplets forming on freshly painted walls? This phenomenon occurs when lime-based paint (calcium hydroxide) reacts with carbon dioxide in the air, forming calcium carbonate and water. The water vaporizes, leaving the surface dry and smooth.
These stories showcase the incredible power and versatility of chemistry. From everyday occurrences to groundbreaking discoveries, chemistry is a fascinating field that continues to shape our world. Who knows what other wonders await us as we continue to explore the depths of this fascinating science?
Example 1: The mystery of how fruits can help to sober you up
Excessive drinking is often called drunkenness, also known as alcohol poisoning. There are many signs of drunkenness, such as increased speech, poor tongue function, hot and numb cheeks, dizziness and instability… These are all signs of drunkenness, and you need to sober up. Many people know that eating some sour fruits or drinking 1-2 liang of clean vinegar can sober up. Why?
Answer:
This is because fruits contain organic acids, for example, apples contain malic acid, citrus contains citric acid, grapes contain tartaric acid, etc., while the main component of wine is ethanol. Organic acids can interact with ethanol to form ester substances, thereby achieving the purpose of sobering up.
Similarly, vinegar can also help sober you up because it contains 3-5% acetic acid, which can react with ethanol to form ethyl acetate. Although sour fruits and vinegar can relieve the anesthetic effect of excessive ethanol, the esterification reaction is interfered by many factors and the effect is not very ideal. Therefore, the best way to prevent drunkenness is not to drink too much.
Example 2: A fire that is difficult to extinguish
The magnesium powder piled up in a factory warehouse was burning, emitting dazzling white light. Next door was a chemical warehouse. If the fire was not put out in time, a bigger fire accident would inevitably occur. The custodian Xiao Zhang used a carbon dioxide fire extinguisher to put out the fire, but it not only failed to put out the fire, but it became more intense. Later, water was poured on the fire, but it did not help. In the end, it was still the experienced firefighters who put out the fire with a very ordinary method, avoiding a major fire. Please think about it, readers, how did the firefighters put out the fire?
Answer:
Experienced firefighters use a lot of yellow sand to put out the fire, isolating the burning magnesium powder from the air and achieving the purpose of extinguishing the fire. Why can only yellow sand be used? Because carbon dioxide reacts with magnesium. Magnesium can burn in carbon dioxide to produce magnesium oxide and elemental carbon. At high temperatures, magnesium can also react with water to produce magnesium oxide and hydrogen.
Example 3: “Laughing Gas”
Everyone’s life is full of laughter, which is controlled by emotions. But there is such a gas that will make you laugh uncontrollably as long as you smell it. Do you believe it?
Answer:
At a chemistry party, performer Xiao Zhang walked to the front of the stage and said to the audience: “I can make all the guests here laugh today.” He then did a few funny moves, which caused laughter from the audience.
He then asked: “Did everyone laugh? Is there anyone who didn’t laugh?”
An audience member raised his hand and said he didn’t laugh. Xiao Zhang invited the audience member to the stage and asked him: “You must not laugh?”
The audience nodded confidently. Xiao Zhang then used his eloquence to say many witty words, but the audience remained indifferent. Xiao Zhang seemed to have no other choice but to shake his head.
After a while, he took out a glass bottle from his pocket and said to the audience, “Smell what’s in this bottle.”
Seeing that there seemed to be nothing in the bottle, the audience boldly opened the bottle stopper and put the bottle mouth to his nose and sniffed a few times. Ho! A miracle happened, the audience began to laugh uncontrollably, and the audience below also laughed with him out of curiosity. After everyone had finished laughing, Xiao Zhang revealed the secret to everyone.
It turned out that Xiao Zhang had collected a colorless gas in a bottle in advance. Its scientific name is nitrous oxide. Because this gas can make people laugh, people often call it “laughing gas”. The audience didn’t know it was a trick and inhaled the laughing gas, so of course they couldn’t help laughing. So who was the first to discover this laughing gas?
One day in 1800, British chemist Davy produced a gas in the laboratory. In order to find out some physical properties of the gas, he sniffed the bottle and suddenly burst into laughter, which puzzled another colleague. At this time, Davy also asked his colleague to smell it, and the colleague also laughed. Thus, Davy discovered “laughing gas”.
One day in 1844, a man who called himself a “chemical magician” used laughing gas to make an advertisement ingeniously: “Tomorrow morning at 9 o’clock, there will be a public performance of inhaling laughing gas in the city hall. I have prepared some laughing gas for the public, which can be used by 20 volunteers. At the same time, 8 strong men will be assigned to maintain order to prevent accidents. I hope the public will watch it enthusiastically and get a sense of novelty and spiritual satisfaction from the laughter.”
After this unique advertisement was posted, it really catered to the psychology of countless curiosity seekers. People rushed to buy tickets to watch this hilarious performance. 20 volunteers came on stage on the spot. When they inhaled the laughing gas, everyone laughed loudly, and some even sang loudly, danced, and made all kinds of strange movements. The audience looked at them and laughed so hard that they couldn’t straighten their backs. The hall was in chaos. At that time, a young man inhaled the laughing gas and not only laughed and shouted, but also jumped wildly involuntarily. He jumped down from the high platform despite the obstruction of 8 big men. As a result, his thigh was fractured, but the young man felt no pain and continued to laugh.
At this time, there was a young dentist at the meeting. Seeing that the wounded man was not in any pain, he immediately thought that this laughing gas not only makes people laugh, but also has the effect of anesthesia and sedation. Otherwise, how could this young man not feel pain after breaking his leg? If I use this laughing gas as an anesthetic for tooth extraction, I will definitely get the same effect. Later, the dentist also used laughing gas for anesthesia when extracting caries for dental patients, and the dental patients did not feel any pain. However, the dosage must be controlled appropriately, otherwise the patient will laugh wildly and it will be difficult to perform the operation.
From then on, the function of nitrous oxide created new developments in the field of anesthesiology history.
Example 4: Light bulb that does not require electricity
A middle school’s interesting chemistry performance is going on enthusiastically. One of the programs is particularly eye-catching. A 200-watt light bulb is hung on a wooden pole. This light bulb emits a dazzling white light. In terms of brightness, ordinary electric lights are far behind it. However, this light bulb does not have any wires connected to it because it is a light bulb that does not use electricity. Please think about it, what is the secret of this light bulb that does not use electricity?
Answer:
It turns out that the light bulb contains magnesium bars and concentrated sulfuric acid, which undergo a violent chemical reaction inside the bulb, causing heat release and light emission. As we all know, concentrated sulfuric acid has strong oxidizing properties, especially when it meets some metals. Metallic magnesium is a substance that is particularly easy to be oxidized, so the two are a natural “match”, and as soon as they meet, a chemical reaction immediately occurs:
Mg+2H2SO4(concentrated)=MgSO4+ SO2+2H2
A large amount of heat is released during the reaction, causing the temperature inside the light bulb to rise sharply, quickly causing the magnesium rod to reach its ignition point. With sufficient oxygen supplied by concentrated sulfuric acid, the magnesium rod burns more vigorously, like a flare.
Example 5: The sinking and floating of an egg
Put a dilute hydrochloric acid solution in a large beaker, and then put a fresh egg in the beaker. It will immediately sink to the bottom. After a while, the egg rises to the surface of the liquid, then sinks to the bottom of the cup, and after a while, the egg floats to the surface of the liquid again. This can be repeated many times. Please analyze why this is the case.
Answer:
Since the main component of egg shell is calcium carbonate, a chemical reaction will occur when it comes into contact with dilute hydrochloric acid to produce calcium chloride and carbon dioxide gas.
CaC03 + 2HCl = CaCl2 + C02 (gas) + H2
The bubbles formed by the carbon dioxide gas are tightly attached to the eggshell, and the buoyancy generated causes the egg to rise. When the egg rises to the surface of the liquid, the pressure on the bubbles is small, and some of the bubbles burst, and the carbon dioxide gas diffuses into the air, thereby reducing the buoyancy and causing the egg to sink again. When it sinks to the bottom of the cup, the dilute acid continues to react chemically with the eggshell, continuously producing carbon dioxide bubbles, which again causes the egg to float up. This cycle of up and down movement repeats, and finally when the eggshell is completely acted upon by the hydrochloric acid, the reaction stops, and the up and down movement of the egg also stops. However, at this time, because the liquid in the cup contains a large amount of calcium chloride and remaining hydrochloric acid, the specific gravity of the liquid is greater than that of the egg, and therefore, the egg eventually floats on top of the liquid.
Example 6: Production of the word eraser
In daily writing, such as when teachers write lesson plans, writers write articles, and students take notes, there are often some mistakes or places that need to be revised. Scribbling and revising will make the article look messy. In particular, there are some erroneous paragraphs that you don’t want to leave traces on the original manuscript, and you can’t erase them with an eraser. What should you do? Using a “word eraser” to erase the original handwriting is the most ideal method. So, let’s make a “word eraser” by ourselves!
Answer:
Before that, we first prepare oxalic acid, distilled water, potassium permanganate, concentrated hydrochloric acid, and bleaching powder. Prepare Liquid A (oxalic acid solution) first, take a small amount of oxalic acid crystals with a spoon, put them in a beaker or conical flask, and add distilled water to dissolve them. Then pour the solution into a dropper bottle and label it Liquid A.
Then prepare ethyl starch (chlorine water or bleaching powder solution).
① Preparation of chlorine water: add a dime of potassium permanganate crystals into the flask, then add concentrated hydrochloric acid into the flask, connect the flask stopper and the catheter, fix it on the asbestos net on the iron stand, and heat it with an alcohol lamp. Lead the catheter into the conical flask filled with distilled water, and after a while, add the newly prepared chlorine water in the conical flask into the second dropping bottle.
② Preparation of bleaching powder solution: If you do not have the conditions to prepare a set of chlorine water production equipment, you can use bleaching powder solution instead of chlorine water. The method of preparing bleaching powder solution is relatively simple. Use a corner spoon to add bleaching powder into a beaker, and then add distilled water to dissolve it. The solubility of bleaching powder is relatively low, so the prepared solution is a little turbid. Pour this solution into the dropper bottle.
In this way, the eraser is ready. To remove handwriting, first drop a drop of liquid A on the handwriting, then drop a drop of liquid B on it, and the handwriting will disappear immediately. Make sure to let it dry before writing the revised handwriting.
Example 7: The Secret of the “Treasure Sword”
In ancient my country, people paid great attention to the use of steel knives. High-quality and sharp steel knives were called “treasure knives”. During the Warring States Period, it was said that people in the Yue State made precious swords such as “Gan Jiang” and “Mo Ye”. They were so sharp that they could “cut iron like mud”. If you put your hair on the blade and blow on it, it would break into two pieces. Of course, the legend is inevitably a bit exaggerated, but it is a fact that the “treasure knives” are sharp. In the past, only a few craftsmen mastered the technology to produce such “treasure knives”. Now we know through scientific research that the main secret of making such “treasure knives” is that they contain elements such as tungsten and molybdenum.
Answer:
In fact, adding tungsten and molybdenum to steel, even in small amounts, such as a few percent or even a few thousandths, will have a significant impact on the properties of the steel. This fact was not recognized until the middle of the 19th century, and then it greatly promoted the development of the tungsten and molybdenum industry. By systematically adding one or more elements such as tungsten and molybdenum – alloying elements – to ordinary steel, various special steels with excellent properties – alloy steels can be produced.
Example 8: Chemistry of the stomach
The stomach has a strong digestive function, which relies on the hydrochloric acid, pepsin and mucus in the stomach. Hydrochloric acid is a highly corrosive acid. When food enters the stomach, the hydrochloric acid will kill the bacteria in the food. The concentration of hydrochloric acid in the stomach is high, enough to dissolve metallic zinc. Pepsin can break down the protein in food. Mucus can wrap up the food, which not only acts as a lubricant, but also protects the gastric mucosa from mechanical damage caused by food. The hydrochloric acid, pepsin and mucus in the stomach work together to digest almost all foods.
Since the stomach has such a strong digestive ability, why can’t it digest itself? This question was raised more than 100 years ago, and there has never been a satisfactory answer.
Answer:
Some scientists believe that the reason why the stomach cannot digest itself is because there is a special substance in the gastric mucosa or gastric juice that can resist the effects of hydrochloric acid and pepsin. Scientists believe that: first, after the stomach wall secretes hydrochloric acid, the hydrochloric acid will not flow back due to the obstruction of the epithelial cells on the surface of the mucosa, and will not corrode the stomach wall. In the event that the epithelial cells are damaged, the mucosa will secrete mucus, which has a certain buffering effect on the hydrochloric acid and can also prevent the hydrochloric acid adhering to the surface of the gastric mucosa from entering the interior. The gastric mucosa also has the ability to “sacrifice pawns to save the chariot”, which allows the epithelial cells to continuously metabolize and renew, preventing pepsin from adsorbing on the mucosa, and achieving the purpose of protecting the stomach wall. In addition, some glycoproteins in the mucus contain a lot of sugar and have a large molecular weight, which can inhibit the activity of pepsin.
Secondly, about 500,000 gastric mucosal cells are shed every minute and can be completely replaced within three days. Such strong regeneration ability can compensate for the temporary damage to the stomach wall caused by digestive juices.
Therefore, under the condition of the party, the stomach cannot digest itself. If the stomach produces too much gastric acid, or if you take medicine on an empty stomach, the stomach wall will be damaged, and the stomach will start to digest itself, and diseases such as gastric ulcers will occur.
Example 9: The indestructible handkerchief
It was Xiaohong’s turn to perform the next show. She took a new and beautiful floral handkerchief, dipped it in a glass of water, squeezed out the water, and then clamped a corner of the handkerchief with pliers and put it on the alcohol to light it. In an instant, all the lights in the hall went out. Only the ignited fire was burning on the stage. After a while, the fire gradually went out, and the audience in the audience felt sorry for the beautiful floral handkerchief being burned in vain. It must have turned to ashes. Suddenly, the lights came on, and the floral handkerchief was intact. What was the reason? The audience may be able to guess!
Answer:
The problem is very simple. It turns out that the glass contains two parts of alcohol and one part of water. The ignition point of alcohol is very low, so it burns very quickly. In addition, the boiling point of alcohol is only 78°C, while the boiling point of water is 100°C. Therefore, alcohol can easily evaporate from the handkerchief and burn, while part of the water remains on the handkerchief to protect it. In addition, during the burning of alcohol, part of the water turns into steam and evaporates. The volatile water vapor takes away part of the heat on the handkerchief, thereby lowering the temperature of the handkerchief and preventing it from reaching the ignition point. The above two factors protect the safety of the handkerchief.
It looks simple, but it took a few handkerchiefs to achieve this effect.
Example 10: Sweating on the Wall
Spring is here, and the walls of Puppy’s house have just been painted with white lime. But two days later, Puppy curiously pointed at the wall and asked his father: “Why is the wall sweating?” His father smiled and answered the question. Who can guess how Puppy’s father answered?
Answer
The puppy’s father replied: The white lime used for painting the wall is calcium hydroxide. After being painted on the wall, it reacts chemically with the carbon dioxide in the air to produce hard calcium carbonate and water. Therefore, the “sweat” on the wall is the result of the chemical reaction to produce water.