Here are a couple of fun chemistry experiments that your kids are sure to love.

Chemical Reaction Experiments for Kids: Green Pennies and Copper-Plated Nails

This awesome experiment is really three chemistry experiments for kids in one! First, in Part 1, an acid-base reaction gives dull pennies their original shine back. Then, in Part 2, we use redox chemistry to turn some of those pennies green. Finally, in Part 3, we coat ordinary steel nails in copper.

What you’ll need:

• About 20 dull pennies
• A shallow bowl (glass or plastic only)
• ¼ cup white vinegar
• 1 teaspoon salt
• A couple of clean steel nails
• Water
• Paper towels

Part 1: Making Dull Pennies Look Shiny and New

1. Combine the vinegar and salt in the bowl and stir to dissolve the salt.
2. Start by dipping a penny halfway into the vinegar solution and holding it there for 20 seconds. Make a note of what you see.
3. Dump the remaining pennies into the bowl and leave them there for 5 minutes.
4. Your pennies should be bright and shiny again! Reserve the solution for Part 3.

What’s going on?

Over time, shiny copper pennies get dull because the metal is gradually oxidized when in contact with air. The chemical reaction for this process is 2 Cu (s) + O₂ (g) –> 2 CuO (s). Copper (II) oxide (CuO) or cupric oxide, the product of this reaction, is dull and greenish. So, a layer of this substance on the surface of the penny makes it look dark brown and dull.

Cupric oxide is also soluble in many acids, including the acetic acid in household vinegar. When you place the dull pennies in the vinegar solution, the acetic acid dissolves the cupric oxide on the surface of the pennies, revealing the shiny pure copper metal underneath.

It’s an acid-base reaction that results in invisible copper ions (Cu²⁺) being left in the vinegar solution: CuO (s) + 2 CH₃COOH (aq) –> Cu(CH₃COO)₂ (aq) + H₂O (l). This will be important in Part 3, so don’t throw this solution away!

Part 2: Green Verdigris Pennies

1. Remove the pennies from the vinegar solution. (Keep it for Part 3.)
2. Place half on a paper towel to dry, and rinse the other half thoroughly in clean water before placing them on a separate paper towel. Label the paper towels so you know which is which.
3. Wait about an hour and note the difference between the two sets of pennies.
4. The unrinsed pennies should have turned a blue-green color!

What’s going on?

The turquoise-colored coating on the unrinsed pennies is a patina called verdigris. You might recognize it as being similar to the color of the Statue of Liberty—that’s verdigris, too! While verdigris can be several different compounds, in this fun chemistry experiment, it is copper (II) acetate, or cupric acetate.

It’s a two-step process. First, the copper metal is oxidized to cupric oxide, exactly the same way it does naturally over time. However, in this experiment, we have sped up the oxidation reaction using salt (NaCl) dissolved in the vinegar. Sodium chloride is an electrolyte, and since oxidation-reduction reactions rely on the movement of electrons, an electrolyte acts as a catalyst by increasing the conductivity of the solution.

In the second step, the acetic acid left on the unrinsed pennies reacts with the cupric oxide to form blue-green cupric acetate: CuO (s) + 2CH₃COOH (aq) –> Cu(CH₃COO)₂ (s) + H₂O (l)

Notice that this is the same reaction that dissolved the cupric oxide in Part 1. The difference is that we’ve taken it out of the aqueous environment. Because of this, the solid cupric acetate remains on the penny as the water evaporates.

Part 3: Copper-Plated Nails

1. Place one nail in the solution from Part 1 so that it is half covered, and completely submerge another nail. Note any changes you see.
2. Leave the nails that way for about 10 minutes. If the color hasn’t changed, come back again in an hour.
3. The parts of the nails in contact with the solution should now be coated in copper!

What’s going on?

Steel is an alloy whose main component metal is iron. When you dip the nails in the penny-cleaning solution, the acid in the vinegar dissolves some of the iron and iron oxides on the surface, leaving it with a negative charge.

Remember those invisible Cu²⁺ ions that were left behind in solution? Those positive ions are attracted to the negative charge on the surface of the nail. As a result, the copper ions are reduced (i.e. gain electrons) to pure copper metal, which is deposited all over the nail.

This is definitely one of the coolest chemistry experiments to do at home, and you probably have everything you need already!

More Chemistry for Kids: Coffee Filter Chromatography

This is one of the easiest chemistry experiments with household items, which makes it suitable for even younger kids. It’s an at-home version of something chemists do in the lab every day: chromatography. Here, you will take a dye from markers and separate it into its component pigments.

( As a fun continuation of this experiment, why not use water to pull the dye off of colored candies, like M&Ms and Skittles? Do you think red M&Ms contain the same pigments as red Skittles? How can you find out? )

What you’ll need:

• Coffee filter
• Ruler
• Scissors
• Pencil
• Non-toxic markers (or other source of dye)
• Water
• Table salt
• A tall glass

What to do:

1. Cut the coffee filter into a square, approximately 3 inches by 3 inches, and use a pencil to lightly mark a line straight across the filter, about a half inch from the edge.
2. Next, use the pencil to make dots for each dye color you are going to test, equally spaced along the pencil line, and label each dot with the name of the color.
3. Now, use each marker to make a small dot on the pencil dot by its corresponding label. Ensure that each colored dot is approximately the same size.
4. Prepare a 1% salt solution by dissolving 1/8 tsp table salt in 3 cups of water. Once the salt is dissolved, pour a small amount of solution into the tall glass. The water level should be approximately ¼ inch high. It is very important that it be lower than the marker dots on your coffee filter.
5. Crease the filter square vertically down the middle so that it can stand upright. Then, gently set it in the glass so that the edge below the marker dots is in the salt solution. Water will start to move up the coffee filter.
6. When the water has almost reached the top of the filter square, remove it from the solution and let it dry.
7. The pigments in the markers should have been carried up the filter, some farther than others. What do you see?

What’s Going On?

This chemistry experiment with household items is a simplified form of chromatography, a technique that real scientists use to separate components of a solution every day.

There are two phenomena at work here. First, capillary action is what causes the liquid to defy gravity and move up the coffee filter. This happens in small tubes (like the porous fibers of the coffee filter) when the intermolecular forces between the liquid and the tube are stronger than the force of gravity pulling on the mass of liquid in the tube.

But the second part is what makes chromatography so useful. Some of your marker colors will have moved higher up the coffee filter than others. It’s likely that a few of them even separated into multiple dyes (e.g. a blue spot and a yellow spot came from your green marker). Chromatography uses the different physical and chemical properties of different molecules to separate them in this way.

Sometimes, a dye will move faster up the coffee filter (the “stationary phase”) simply because it is a smaller molecule and weighs less. Usually, though, molecules are separated by their affinity for the stationary phase or the “mobile phase” (the salt solution in our case).

More polar molecules will have a stronger affinity for the positive and negative ions in the salt water, for example, and will be carried up the filter more easily. Nonpolar molecules, on the other hand, will not have any attraction to these charges, and will not get swept away by the solution so quickly.

Your Own All-Natural pH Indicator

Tons of household liquids “behave” the way they do because they are acidic, neutral, or basic. You could check the pH of these liquids with test strips or an indicator solution you buy at a pool supply store or the pet shop. But did you know you can do this with an ordinary vegetable?

The gorgeous colors in this simple experiment make it chemistry for kids at its best!

What you’ll need:

• Half a red cabbage
• 2-3 cups boiling water
• Strainer
• Various household liquids for testing (e.g. plain water, lemon juice, baking soda solution)
• One clear glass for each liquid
• Additional water for diluting

What to do:

1. Prepare the pH indicator from the cabbage. To do this, chop the cabbage into small pieces, cover in a saucepan with boiling water, and let cool. Strain to separate the liquid, which should be dark purple. This is your indicator solution.
2. Dilute a small amount of your household substances in water in separate glasses. Make sure to label them so you know what’s what. It’s a good idea to have one glass of plain water to act as a control.
3. Predict what color each liquid will turn when you add the pH indicator, and then see if you’re right by pouring a small amount into each glass.
4. Neutral liquids should be purple, like the indicator itself. Acidic liquids should turn hot pink, and basic liquids should turn blue!

What’s going on?

Acidity, for the purposes of pH, is a measure of hydrogen ions (H⁺) in a solution. A pH of 7 is considered neutral. If a liquid is acidic, its pH will be between 0 and 7, and if a liquid is basic or alkaline, its pH will be between 7 and 14.

A pH indicator works by reacting with acidic (H⁺) and basic (OH^–) ions in a solution; the product of that reaction is a different color than it was originally, thus indicating whether the solution was basic or acidic.

In red cabbage, the plant pigment anthocyanin has a molecular structure that allows it to act as both a base (reacting with acids) and an acid (reacting with bases). It therefore has three different forms, each with a different color, depending on the number of acidic hydrogens it contains (fully protonated in an acidic environment, partially protonated in a neutral environment, and fully deprotonated in an alkaline environment).

Final Thoughts on Chemistry for Kids

These fun chemistry experiments with household items are simple, safe and visually interesting for kids. But to make sure they get the most out of it, don’t forget to ask them questions (and do your best to answer theirs). What do they see? Why might that be happening? What would happen if you changed the conditions slightly?

You’ll have a budding scientist before you know it!

Also, make sure to check some of the more general science experiments that you can do at home that we have also published recently.

The post Awesome Chemistry Experiments For Kids To Do At Home appeared first on Chemistry Hall.

We have reviewed and updated this guide recently, so it is ready for 2020. You can check the best available options right now.

Get ready to share a great adventure into chemistry together with your kids!

Why Do Chemistry Experiments at Home?

Kids are naturally curious about the world around them. Satisfying and encouraging that curiosity will help lay the foundation for a lifelong love of learning.

Chemistry is driving practically everything that happens in the universe, and the best way to learn it is to see it in action. Think back to your own schooldays. What parts of science class were the most memorable? The experiments and demonstrations!

Chemistry is an empirical or experimental science, and it is extremely difficult to make it enjoyable for a kid using only theory, or textbook explanation. Many chemists even admit to not like chemistry very much when they were kids! This was because their learning experience lacked of experiments.

Basically, the reason to find the best chemistry set for kids with age-appropriate experiments is that they are educational and totally cool. Students of all levels can learn important science concepts and have tons of fun doing it.

We have previously covered how to set up a home chemistry lab, but today we focus on another very important topic: learning together with our kids!

And this kind of sets go beyond learning chemistry. If you are interested in other fields of science, you should go and get your hands into a science kit.

If you are looking for something to give as a gift to a chemist, check out this gift review!

In this post, we’ve got our pick for the best chemistry set for kids, as well as detailed reviews for eight different chemistry kit products, all ideal for classroom or home use.

Our Top Choice for Best Overall Chemistry Kit

As always, we start this review post with our number one pick. Today, that designation goes to the Thames & Kosmos Chem C2000 kit. This would be considered the intermediate chemistry set, between the C1000 and the C3000 products.

Thames & Kosmos Chem C2000 (V 2.0)

We rate this best overall because of the amazing number of projects, quality materials and full-color experiment manual. It is on the higher end of the price range among the kits in this article, but with everything you get, it is a great value.

Chem C2000 was the best in 2019, and is still the best option out there in 2020.

The Chem C2000 chemistry set includes around 250 experiments with professional quality equipment. As such, it is ideal for homeschooling and traditional classrooms alike.

Thames & Kosmos recommend this kit for ages 11 and up; after all, there are some pretty serious chemicals in here, not to mention an alcohol burner for experiments that require heat.

Quick Comparison Table

The Best Chemistry Sets for Kids

Now, starting with our top pick, we’ve got detailed reviews of eight products which provide fun chemistry experiments for kids of all ages.

1. Thames & Kosmos Chem C2000

Thames & Kosmos offer a range of Chem kids’ science kits, and the C2000 falls right in the middle in terms of extensiveness, level, and price. It comes with the equipment and supplies you need for some 250 experiments with a comprehensive lab manual to guide budding scientists through each activity.

Thames & Kosmos Chem C2000

We would rate this as the ideal beginner chemistry set for older elementary school and up. Thames & Kosmos are famous for their award-winning products, so it’s no wonder they rolled out the best science kit for kids. Both this and the more basic C1000 kit have won awards from the Parents’ Choice Foundation.

Although it does not have as many experiments as the C3000 kit, it is very complete and very professional. It is recommended for ages 11 and up, but honestly, adults are just as likely to find this chemistry kit enjoyable and educational as children are.

Of particular note in the C2000 set is the alcohol burner, which greatly expands the number of possible experiments by providing a heat source.

2. Thames & Kosmos Chem C3000

This product is, of course, the more advanced premium option from Thames & Kosmos. Compared to the C2000 model, this chemistry kit has about 333 experiments, with extremely high quality equipment.

Thames & Kosmos Chem C3000

If you don’t mind the higher price point, this would definitely be the best chemistry set for adults of all the products on this list. It is just about the closest thing you’ll find to a professional chemistry set out there.

The C3000 model is recommended for ages 12 and up, and its experiments cover some fairly advanced topics. It would make a great companion to high school science, and would be right at home in the classroom as well.

If you are looking for a more advanced chemistry set for teenagers, this is probably a very nice bet.

3. Thames & Kosmos Chem C1000

Once again, another product from Thames & Kosmos that ranks among the best science kits for kids. Unlike its higher-end counterparts, the C1000 has just 125 experiments. However, this is still a very complete set, recommended for ages 10 and up.

Thames & Kosmos Chem C1000

Perhaps the most obvious benefit of the C1000 chemistry set compared to the other to is its more affordable price. Considering everything you get, we would still call the C2000 a better overall value, but this is another excellent choice.

Also, the Parents’ Choice Foundation has dubbed this one of the best chemistry sets for kids, too, by giving it their gold award.

4. Ben Franklin Toys Chemistry Lab Pad Science Kit

This product from Ben Franklin Toys is one of several options for chemistry kits for kids in preschool and early elementary school. Accordingly, it puts a focus on safety and exploration, and it is designed for children ages 5 and older.

Ben Franklin Toys Chemistry Lab Pad Science Kit

The distinguishing feature of the Lab Pad Science Kit is, you guessed it, the lab pad. Parents and preschool teachers will appreciate the lab pad, because it serves as both a work surface for experiments and storage for all the included equipment. As a result, everything stays nice and organized in between science days.

However, the experiments in this product are very limited. In contrast to the other chemistry sets on this list—even the ones designed for younger kids—it only has around 12 activities to do. The price for this product is in the middle of the range, but if you are looking for a great variety of experiments to do with your kids, then it might not be the best value.

5. Learn & Climb Kids Science Kit

Another chemistry set for kids designed for the preschool and kindergarten age group, the Learn & Climb Fun with Science kit is suitable for ages 5 and up.

Learn & Climb Kids Science Kit

Unlike the previous product, Learn & Climb provides a much more complete kit. It contains over 60 experiments, compared to just 12 in the Ben Franklin Toys product, and it retails for a lower price.

In fact, we would rate this as the best chemistry set for kids between the ages of 5 and 10. The number and variety of activities is quite impressive, it is very affordable, and it is designed to help kids learn and explore independently. On this last point, the kit includes a kid-friendly experiment manual and an instructional DVD to guide young scientists through each project.

6. Learning Resources Primary Science Deluxe Lab Set

If the Learn & Climb science kit is the best option for elementary school-aged children, then this lab set from Learning Resources is the best chemistry set for kids who are still in preschool. Designed for children as young as 3 years old, it is perfect for the youngest scientists.

Learning Resources Primary Science Deluxe Lab Set

This kit comes with 20 double-sided activity cards that guide students through experiments with step by step instructions. Altogether, it’s a great kit for giving kids their first exposure to real scientific equipment, like test tubes, flasks, funnels, and even a “science view scope” that looks like a microscope.

So, if you want to encourage scientific exploration in your children or students between the ages of 3 and 5, then this would be our top recommendation.

7. Dan & Darci Light Up Crystal Growing Kit

One of the most rewarding and visually impressive science experiments you can do with your kids is crystal growing. While natural crystals take thousands of years to form in the ground, crystal growing kits like this one from Dan & Darci take just one week or less to form beautiful crystals that will fascinate children and adults alike.

Light-up Crystal Growing Kit for Kids

Although the kit is not recommended for use by kids under 8 years old, your younger kids can still get excited checking the crystals each day to see how much they’ve grown.

The Dan & Darci crystal growing kit is very reasonably priced for this type of product. It comes with materials to grow three crystals: one red, one blue, and one colorless. All you have to do is add boiling water and follow the instructions.

Arguably the most standout feature of this specific crystal growing kit is the LED light display. Once your crystals have finished growing, simply use the included USB charging cable to charge the LED display, and then set your crystals on top and enjoy the beautiful results.

8. Happy Atoms Magnetic Molecular Modeling Complete Set

When kids start learning about atoms and molecules in middle and high school, the new information can be very abstract and overwhelming. Don’t let this discourage them! Instead, help them feel curious and confident by putting those molecules right in their hands.

Happy Atoms Magnetic Molecular Modeling Complete Set

This Happy Atoms kit might seem somewhat expensive for a molecular modeling kit; however, it has a very innovative special feature that accounts for the more premium price. In addition to the magnetic atoms and bonds, it comes with a scanning mat and a free app download that will scan and identify the molecules your child builds.

Because of this, it is a great tool for kids aged 10-17 as they go through their first dedicated chemistry classes. Also, it comes with 216 enrichment activities that are fun and sure to foster a love of science.

If you want more info on molecular modeling kits, make sure to check our previous review.

FAQ (Frequently Asked Questions)

In all cases, any time you are performing chemistry experiments, always make sure that you wear lab safety glasses. Protect your eyes (and your kid’s) at all costs.

Choosing the Best Chemistry Set for Kids

Luckily, this is a very easy choice for parents and teachers to make. After all, the main factor to consider is the age of the children who will be using the kit.

If your young scientist is at least 10 years old, then one of the Thames & Kosmos chemistry sets will be most appropriate for general chemistry experiments, especially the Thames & Kosmos Chem C2000 model. This is a great option that even adults will enjoy. The chemistry kits from this series are a great complement for learning chemistry in high school too.

If they are taking chemistry in high school, teenagers would also strongly benefit from the Happy Atoms molecular modeling kit and its companion mobile app.

For elementary-aged kids, approximately ages 5-10, we would recommend the Learn & Climb Kids Science Kit. This is because of its excellent array of experiments compared to similar products, its great value, and its clear focus on kids.

Finally, the Learning Resources Primary Science Deluxe Lab Set is certainly the best chemistry set for kids who are still in preschool and too young for the Learn & Climb kit. With visual instructions, bright colors, and safe experiments, it’s ideal for ages 3+.

If you want to check out some chemistry experiments that you can do at home without having to purchase any kit, make sure to check these examples.

So you see, there are great options available to do fun chemistry at home no matter where you kids are on their learning journey. These experiments are so cool, they won’t even realize they’re educational!

The post The Best Chemistry Set for Kids (and Adults!) appeared first on Chemistry Hall.

Let’s set the record straight here. Applying your knowledge of chemistry can help you cut through the marketing hype and fear mongering. The truth is often simpler than you might expect.

What Is Distilled Water?

Distilled water is simply water that has been purified through a process of distillation. That means it has been boiled, and the resulting steam has been collected and condensed, leaving you with what is, in theory, perfectly pure water (it is not a complicated set up, you could even do it at home).

What does “perfectly pure” mean, in this case? Consider tap water, spring water, or any other water you might encounter in daily life. All of this water has some amount of other “stuff” in it besides hydrogen and oxygen.

Some of it might be stuff you can see, like algae in lake water, for example. But most of it will be invisible to the naked eye: dissolved minerals like calcium, sodium, potassium and magnesium, chlorides and bicarbonates, and sometimes additives like chlorine and fluoride in tap water in some regions.

There may even be microscopic critters swimming around in the water. Most of them are harmless, but some pathogenic microorganisms cause very serious illness (this is why so many cities treat their water supplies with a small amount of chlorine).

So, the perfectly pure water that comes from distillation is missing all of the above—it contains no minerals, no bacteria, no nothing. Just plain ol’ H₂O.

Is it Safe to Drink?

The short answer is, yes, it’s safe to drink distilled water. But you might not want to make a habit of it.

Typically, distilled water of different qualities is employed to perform analytical chemistry techniques.

First of all, it’s not going to be any better for you than your regular tap water (assuming you are in an area where the water is safe to drink), and it can actually have certain negative long-term effects in some people.

Because it contains no minerals (i.e. electrolytes), it may be harder for your body to stay hydrated drinking distilled water, or you may get muscle cramps because of low calcium and magnesium. Still, these side effects are far from universal and certainly no reason to avoid distilled water if it is the only uncontaminated source available. You can always replenish electrolytes through food.

To illustrate just how safe it really is, consider that distilled water is often used to prepare formula for infants with particularly weak immune systems.

It has plenty of other uses, too. It’s essential for laboratory tests and chemical preparations like cosmetics, and it is very useful in cars and domestic appliances for reducing limescale and other mineral deposits.

But it’s not the best for drinking if you care at all about how your water tastes. If you look closely at any bottle of purified drinking water, you’ll see that, after purification, minerals have been added back into the water. This is because distilled water, without any minerals, tastes bland and flat.

Finally, it’s a lot more expensive than tap water. It’s worth paying extra to keep your car and clothes iron working smoothly, but for drinking? Why pay more for water that tastes bad and offers no benefits unless it’s really necessary?

What About Alkaline Water?

Speaking of water that is unnecessarily expensive and doesn’t offer any benefits…

I don’t know when this idea first came onto the scene, but I first heard someone peddling the idea of acidic and alkaline diets circa 2007. It didn’t seem terribly harmful at first—the proposed “alkaline diet” was rich in fresh vegetables and fruits, low in sugar and processed foods, and really an undeniably healthy way of eating—but this notion grabbed a foothold and is now being used to scam people out of their money with false health claims.

So now, over a decade later, alkaline water is being sold everywhere you look for exorbitant amounts of money compared to tap water. Depending on who you ask, this water will make sure your blood maintains its proper pH (very slightly basic), doing everything from reducing systemic inflammation to preventing cancer.

For anyone with a rudimentary understanding of chemistry and biochemistry, this is simply preposterous.

Yes, an alteration in your body’s pH is a big problem, but this does not happen as a result of consuming normal foods or drinks. We all eat and drink acidic and alkaline things every single day without any effect on the pH of our bodies. This is because the human body contains numerous regulatory mechanisms and buffering systems to prevent the things we ingest from affecting the pH of our blood or cells.

The body rids itself of excess acid by exhaling carbon dioxide, by excreting it through the kidneys, or by retaining bicarbonate.

So, what happens if you do drink alkaline water? Think about where that water is going: straight into the highly acidic environment of your stomach. Your body has its own built-in water alkalinization system! Before it is absorbed by the colon, the acidic water from your stomach is neutralized by bicarbonate secretions from the pancreas.

Drinking Distilled Water: Water Quality

With all of this in mind, we can say that, in general, it is safe to drink distilled water. Most tap water, however, is equally safe to drink, tastes better and is much cheaper. But if you know that the area you are in does not have safe drinking water, you should not hesitate to drink distilled water if it is the only clean water available.

I guess the same could be said about alkaline water—if there’s nothing else safe to drink, by all means—but that’s the only good reason to do it. Put your chemistry knowledge to use, don’t be fooled by marketing gimmicks, and save your money.

If you want to impress a chemist with a gift, please, don’t even think about these kinds of scammy trends, there are so much better options!

The post Is It Safe To Drink Distilled Water? appeared first on Chemistry Hall.

While not all historians agree, many consider alchemy to be the proto-science of chemistry, its forerunner. The transition from alchemy to chemistry is, in any case, a fuzzy one, and the decline in alchemy’s popularity more or less coincides with the rise of true or modern chemistry.

Since then, although no one puts much stock in alchemy as a science any longer, technology has advanced to the point today that one centuries-old dream of alchemy—turning other metals into gold—has finally become a reality.

In this post, we’ll look at how alchemy came to be, how the study of matter transitioned to the science of chemistry we know today, and how humans finally discovered how to turn lead into gold.

Ancient Examples of Chemistry

The dawn of what we would consider chemistry by modern standards did not take place until the 16^th century at the earliest. However, whether they understood it or not, humans have been using the science to improve their lives for millennia.

Seemingly simple processes, like preserving foods or making soap, rely on chemical concepts that would not be fully understood until thousands of years after people started to use them. Later came more advanced techniques, such as extracting plant essences for medicines and perfumes, the ability to extract iron from iron ore, the science of metallurgy in general, and the creation of metal alloys (most notably, bronze, for which the Bronze Age is named) and glass.

Meanwhile, classical thinkers such as Empedocles and Democritus developed philosophical theories about the nature of matter, including the concept of the four elemental substances—air, water, earth and fire—and the theory of the atom, an indivisible and indestructible particle, respectively. Many principles from Greek philosophy would persist over the centuries in the now-burgeoning field of alchemy.

Alchemy, the Mystical Science of Transmutation

Most people associate alchemy with two pursuits: turning lead into gold and finding the source of human immortality. But there was actually a lot more going on in alchemy, and it was a science that was studied and practiced differently in many parts of the world.

Alchemy in the West had its roots in in the city of Alexandria in ancient Egypt. It is hard to set an exact year when it began, but because of the nature of the discipline, some people date it back to the beginnings of metallurgy, around 3500 B.C.E. However, in addition to the technological aspect, alchemy was also built on a strong foundation of philosophy and esoterism. In fact, by the 7^th century, the mysticism of Western alchemy far outweighed its technical concepts.

Independently from the Western world, alchemy was also being studied in East Asia and on the Indian subcontinent, although with slightly different principles, as would be expected. Like its Western counterpart, Indian alchemy sought to transform base metals into gold and find the secret to eternal youth. In China, alchemy had a stronger connection to medicine, and arguably resulted in more useful knowledge and inventions, such as gunpowder.

But what comes to mind for most of us when we think of alchemy is medieval Europe, and alchemy likely would have never reached that time and place without the contributions of the Islamic World after the fall of the Roman Empire. In fact, the word alchemy has its origins in the Arabic language. Jabir ibn Hayyan, now considered by some to be the father of chemistry, was among the first to attempt to standardize alchemy with controlled experimentation and a scientific approach in the late 8^th century.

The Beginnings of Modern Chemistry

Until the 18^th century, alchemy and chemistry were not treated as separate disciplines, and both fell under the term chymistry. There were numerous flaws with alchemy experimental design and practice that eventually made it necessary for a new, more rigorous study of matter to emerge.

Works explaining chemical phenomena without the mysticism of alchemy date back to at least the 16^th century, including an extremely important work by Georg Agricola on the science of metallurgy, and the origins of what we now call the scientific method by Sir Francis Bacon in 1605.

But it wasn’t until a few decades later that the first modern chemists, such as Robert Boyle, would advance the field of chemistry and fully distinguish it from alchemy, in part by arguing that there was no evidence to support the existence of only the four classical elements of water, air, earth and fire. He was also instrumental in creating rigorous standards for experiments, and he believed that a theory could not be accepted as true until it was supported by experimental evidence.

Some of the discoveries made during this time were remarkable, while others sound downright silly to us nowadays. In the late 18^th century, Antoine-Laurent de Lavoisier showed that sediment in boiling water was not a result of water element transmuting into earth element, but was in fact just from the container it was being boiled in. But he also established and experimentally proved Lavoisier’s Law, also known as the Law of Conservation of Mass, which is certainly nothing to laugh at.

Can We Turn Lead into Gold?

While alchemy could not accomplish this, modern nuclear physics techniques can be used to change the nucleus of an atom, such as lead, and turn it into another, such as gold. However, this process is far from being economically feasible.

Turning Lead into Gold… with Nuclear Physics!

By the turn of the 20^th century, after alchemy had long fallen out of fashion among scholars, physicists Frederick Soddy and Ernest Rutherford witnessed how the element thorium turned into radium through radioactivity. Soddy immediately recognized this as transmutation, but Rutherford was more apprehensive: “For Christ’s sake, Soddy, don’t call it transmutation. They’ll have our heads off as alchemists.”

As we mentioned briefly in another post, 100 fun chemistry facts, the hallmark goal of alchemy, turning lead into gold, is actually possible. It’s just not something that can be accomplished with chemistry. The answer, it turns out, lies in physics through nuclear transmutation.

Nuclear transmutation is a process that occurs naturally in the universe, in the centers of stars, supernova explosions, etc., where it is called nucleosynthesis. This is how (essentially) every element other than hydrogen and helium came into existence. But now, using particle accelerators, we can recreate this natural process and literally turn one element into another.

The reason, of course, is that an element is defined by the number of protons in its nucleus, which we refer to as the element’s atomic number. Inside stars, the incredible heat and mass allow nuclear fusion reactions to occur, by which, for example, three helium nuclei, with two protons each, come together to form a carbon nucleus with six protons. In the case of turning lead into gold, particle accelerators make it possible to knock a few protons out of the nucleus of a lead atom until only 79 protons remain—gold!

Of course, just because it’s possible doesn’t mean it makes economic sense to do it. But even so, it’s curious how the evolution of science has brought us to this point, turning something that would have been thought possible only with actual magic into something totally achievable.

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Making soap at home is a fun and crafty way to get some firsthand chemistry experience and enjoy the fruits of your labor.

Soap and soapmaking encompass many chemistry concepts:

• Acids, Bases and Salts
• Biochemistry: Lipids
• Organic Chemistry: Esters, Carboxylic Acids and Alcohols
• Hydrolysis
• Emulsification
• Hydrophilic/Hydrophobic Interactions

But don’t be intimidated—the actual process of making homemade soap is easier than you think!

Read on for a summary of the chemistry behind soapmaking, the chemical reaction that is used to make soap, and the science of how soap works. Most of these concepts are further expanded in any organic chemistry textbooks, which we have reviewed here.

Otherwise, skip to the bottom of the post for a simple beginner-friendly DIY soap recipe.

It is a fun experiment with kids, but always supervised! If you want to do chemistry with children, make sure to get one of the best chemistry sets for kids and adults out there!

The Chemistry of Soapmaking: Saponification

The chemical reaction that produces soap is so ancient and characteristic that its name literally means “to turn into soap”.

Saponification, from sapo, the Latin word for soap, is one of the more memorable chemical reactions learned in the first semester of organic chemistry because of its obvious applications in everyday life.

Here is a Summary of the Overall Reaction

First, we begin with a triglyceride (the fatty molecules found in vegetable oils and animal fats). A strong base is added, which breaks the ester bonds of the triglyceride into three carboxylic acids and glyceroxide. Finally, after proton exchange, the products are three carboxylic acid salts and glycerol.

Explanation of the Saponification Reaction Mechanism

Saponification is an alkaline hydrolysis of an ester. You may recall that the formation of an ester is a dehydration reaction between a carboxylic acid and an alcohol.

In biochemistry, this reaction creates a triglyceride from three free fatty acid chains and one molecule of glycerol. Saponification uses a strong base to essentially undo that reaction. We have explored this and other simple reactions in this tutorial review about organic chemistry concepts.

Remember that a carbonyl carbon, such as the one in an ester bond, has a partial positive charge due to both resonance and the greater electronegativity of the bonded oxygen. Because of this, it is a good target of nucleophilic attack by the hydroxide ion. The product of this step is an orthoester intermediate (note the negative charge on the former carboxyl oxygen).

Remember that oxygen is most stable when it has two bonds and two lone pairs of electrons. Its electrons rearrange in order to achieve this stability, reforming the double bond with carbon to make a carboxylic acid and expelling the other half of the ester as an alkoxide, in a second step called “elimination” (the conjugate base of an alcohol).

We know that alcohols in general are very weak acids. Their conjugate bases, alkoxides, are therefore quite strong. As a result, proton exchange takes place, and the acidic proton of the carboxylic acid is readily donated to the alkoxide. This results on the formation of an alcohol, plus the sodium or potassium salt of the carboxylic acid.

Products of Saponification

This same reaction is occurring at all three ester bonds in a triglyceride during saponification. The three resulting fatty acid salts are also known as soap salts. Their properties are highly dependent on the number of carbons in the fatty acid chain and the degree of saturation.

Longer carbon chains (stearic acid, C18, for instance) tend to yield soaps that are harder and less soluble.

On the other hand, unsaturated fatty acids will yield a softer soap with a lower melting point. Some fatty acid salts are more cleansing than conditioning, and vice versa. Similarly, some will work up a nice, rich lather, while others will not. It’s important to consider these effects when deciding which fats and oils to use in a soap recipe.

How does soap work?

Take a look at the molecular structure of this soap salt:

Is this molecule polar, or is it non-polar? The answer is, both! At the top right, the carboxylate, acting as the anion in this sodium salt, is a very polar functional group. However, the rest of that long hydrocarbon chain is non-polar.

This type of compounds are called amphipathic.

Everyone knows that oil and water don’t mix, but not everyone knows that the reason for this is the polarity (or lack thereof) of each substance. As a chemistry student, you have probably already learned that like dissolves like, and that polar molecules are hydrophilic (water-loving) while nonpolar molecules are hydrophobic (water-fearing).

You can probably see where this is going… Soap works by allowing hydrophobic substances, like grease and oil, to dissolve in water. Its two ends, one polar and the other nonpolar, allow it to mix with both water and oil. It does this by forming tiny spherical structures called micelles.

In this cross-section of a micelle, you can see the hydrophobic (nonpolar) hydrocarbon chains inside the sphere, while the hydrophilic (polar) ends form the surface. When you wash a greasy pan with soapy water, the grease is attracted to the hydrophobic ends, trapping it inside these micelles. Since the surface of the micelle is polar, it is soluble in water and can now be easily rinsed away.

Soap is also a natural surfactant, which means it reduces the surface tension of water, effectively making water “wetter”. The “wetter” the water is, the better its solvent properties are, and the better it cleans.

Chemistry at Home: How to Make Your Own Soap

Now, let’s put all this chemistry knowledge into action and make some homemade soap!

This DIY (do it yourself) soap recipe is a very basic one that is perfect for beginners. You will need some basic equipment and a few easily accessible ingredients:

Soapmaking Equipment

• Safety goggles and gloves
• Kitchen scale
• Pitcher*
• Jar*
• Large pot or bowl*
• Thermometer
• Mixing spoons*
• Immersion blender (stick blender)
• Rubber spatula
• Soap molds

* Make sure you use nonreactive materials, like plastic or glass.

You can find our personal recommendations on home chemistry labware here. It would be ideal to be able to use appropriate beakers or flasks for this experiments. But if you don’t have access to those yet, you can get away with the household items listed above.

Lye is caustic (very basic) and can react with many things, as metals (or you skin!). This reaction is exothermic, and the rapid temperature change may cause low-quality glass containers to crack.

Basic Soap Ingredients:

• 500 g of olive oil
• 100 g of coconut oil
• 80 g of lye (NaOH, caustic soda)
• 200 mL of water

Keep in mind that, while you can use practically any type of oil or fat to make soap, they will have vastly different properties and may require different amounts of lye. If you use different oils, make sure you use a lye calculator to ensure you aren’t using too much. Having excess oil in your soap is not a big deal, but having excess lye is!

Instructions:

1. Prepare the lye/NaOH solution. Weigh the water in the pitcher. Separately, weigh the NaOH into the jar. Then, slowly add the NaOH to the water. DO NOT ADD THE WATER TO THE LYE! Remember how they made you memorize “add acid to water, not water to acid” in your chemistry lab’s safety module? The same goes for bases. A strong base like NaOH is highly reactive by definition. That means a LOT of energy is released when it makes contact with water. If you do this step backwards, the mixture will quickly heat up. This might end-up in a caustic soda geyser, which can easily cause a chemical burn. When you add NaOH to water, there will still be heat release, but it will be much less dangerous. Carefully stir to dissolve (rinse the spoon immediately after mixing). This solution can get to almost boiling temperature all by itself, so you may need to allow it to cool down slightly until you can easily handle the pitcher.
2. Weigh out and mix your oils in the pot or bowl. This will be easier if you warm the coconut oil up a bit first until it melts.
3. Carefully add the NaOH solution to the oil mixture and gently mix with a spoon until it gives an homogeneous mixture.
4. Now you can pull out your stick blender and start the emulsifying process. Remember, you are blending a highly caustic mixture right now, so keep your distance and try not to splatter.
5. After a few minutes of blending, the mixture should start to thicken, indicating that the saponification reaction is underway. Optionally, this is when you can add other ingredients to customize your soap, like essential oils, colorants, mix-ins, etc. Otherwise, you can proceed with transferring the soap to whatever you are using as molds. Silicone baking molds work great for this. Use a rubber spatula to get every last bit out and facilitate cleanup.
6. Let your soap harden for at least 24 hours before trying to remove it from the mold. Once it is hard enough to handle, you can cut it into different shapes/sizes if desired.
7. Finally, the soap needs to cure for about one month to be sure the saponification reaction is complete and to dry out the excess water. Once it’s fully cured, you can enjoy using your homemade soap!

And that is pretty much it! As you can see, it is an easy procedure.

Now that you know how to make your own soap, and you understand the chemistry behind it, time to put the experimental procedure into practice!

Let us know in the comments if you have any question or suggestion. Also, feel free to share the results of your first batch of soap!

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