Chemistry Archives

When An Experiment Fails

In our homeschool STEM Class, I attempted a little chemistry demonstration – just for fun. I’d originally read about the pumpkin demo here, Rainbow Fire, and I did the experiment as described but as the kids can attest, it didn’t work. On the drive home, my kiddos hypothesized that the fact that I waited a little while for everyone to get settled may have caused the hand sanitizer to evaporate. Upon further investigation, however, perhaps I was missing a key chemical. Another site I found, Green Fire, suggested the use of Heet (methanol). I will have to try again. If any of you give this a try, please let me know what you discover. 🙂

The fact that it didn’t work out though is perfect science (though very embarrassing when done as a class demonstration). When an experiment doesn’t go as planned, however hard to admit, it is actually great. It gives you the chance to go back and really figure it out. There is always an answer for why it didn’t work. You often learn more when it doesn’t go as planned.

Later that afternoon, Buddy was working on an aeronautics project (he’s trying to make an airplane with cardboard, rubber bands, and plastic propellers). When his design doesn’t work out, he gets very frustrated and laments, “I wasted so much time on this! I wasted all this glue!” (or tape, or whatever materials he used). It is difficult to console him but with my own failure earlier that morning, I had an example with which to show it happens to all of us.

Recently, another activity seemingly failed and I thought I would share our process of discovery with you …

Signs of Fall

One of the extension activities I had suggested to my STEM students when we were covering plants was a chromatography activity to investigate the pigments in leaves, Signs of Fall (scroll down for the activity “Invisible Changes”). Another link, with the same title, Signs of Fall, provides a PDF download for a student page with guiding observation questions.

My daughter and I worked together to set up the investigation just as it was described. She was even careful to measure an exact amount of isopropyl alcohol into each jar. We then placed a strip of coffee filter into each jar, taping it into place to secure it and then capping each jar with a small piece of aluminum foil. We left it overnight but there was not a single strip with any color pigment. We thereby walked away, shrugging our shoulders. Another failed experiment. This was getting frustrating.

I couldn’t let this one go, however. We must have overlooked something. I thereby left it set up on the kitchen counter for another day or two while we contemplated and brainstormed what we might have done wrong. When we happened to peek into the jars a couple of days later, we surmised that perhaps we had put the coffee strips into the jars too soon – before the heat of the water bath had had time to activate the pigments because the liquid in the jars was now clearly colored when before it had remained clear.

We thereby pulled off the aluminum foil, discarded our first strips and inserted new ones. We checked the progress of our test a few hours later …

Whoa-lah!

If chromatography is something you’d like to investigate further, you might also consider this activity, Rainbow Candies: A Candy Chromatography Experiment for Kids. It is a great way to use up some of that leftover Halloween candy that may be lying about.

An expanded version of this lesson is available in the Science Logic curriculum
Life Logic: Plenty O’Plants.

With Independence Day upon us this week, the fireworks stands are popping up all over town. With the dry weather and heat wave many are experiencing this year, I am confidant many cities will be enforcing strict prohibitions against fireworks. Why not then take the time to explore the science of fireworks and perhaps try making a few simple ones yourself?

Learn about the science of fireworks with this awesome video. How do fireworks work? Where do the cool colors come from? What makes the big explosions?

Creating firework colors requires considerable art and application of science. Excluding propellants or special effects, the points of light ejected from fireworks, termed ‘stars’, generally require an oxygen-producer, fuel, binder (to keep everything where it needs to be), and a color producer.

The bright colors visible when fireworks explode are a result of pyrotechnic stars —pellets of chemicals that generate certain colors or produce sparking effects when burned. When the bursting charge is ignited, the main fuel explodes first, transferring energy to the colorant chemicals, which prompts these chemicals’ electrons to move into an excited state. Then, moments later, when the colorant chemicals cool and the electrons fall back to their base state, they release the extra energy as colorful radiation when they are flying through the sky. The specific color depends on the chemical:

To achieve unusually-shaped fireworks, such as double-rings, hearts or stars, technicians pack the fuel and colorant chemicals inside a tube in different formations. Chemists design fireworks to burn as slowly as possible, rather than explode rapidly – a slower burn means that a visual effect will last longer and cover a greater area of the sky. To achieve this, the fuel and oxidizer chemicals used are relatively large-grained, about the size of a grain of sand. Additionally, chemists avoid mixing the fuel and oxidizer together thoroughly, making it more difficult for them to burn.

Flame Photometry

If you wish to delve into the science of fireworks even further, consider undertaking flame photometry experiments. Rainbow Fire, is an exciting activity kit that you may wish to consider; it is available for purchase at Science Buddies. The necessary materials and the experimental procedure are outlined for you on their website. Of course, adult supervision is required. The four chemicals used in the kit are:

Copper sulfate
Strontium chloride
Boric acid
Sodium chloride

Things to Ponder

How are the colors produced by a chemical when it burns related to the atomic structure of the chemical?
What is flame spectrometry and how is it used by physicists and chemists?
How does this science project relate to what astronomers do when they are trying to identify the atomic makeup of a star?
What are metal ions? In the chemicals used in this science project, which elements in the compounds are metals?

Black Snake Fireworks

Do you remember watching long carbon worms emerge from growing tablets our parents lit with matches on the 4th of July? For a simple do-it-yourself recipe, a homemade black snake is sure to delight.

What a joy teaching environmental science has been. Thus far, we’ve learned about the changes in environmental policy and how the Boy Scouts of America have contributed to environmental conservation practices. We have also learned about pollination, environmental changes, and threatened and endangered species.

Today, our focus shifts to acid rain, pollution prevention, and conservation practices we can engage in ourselves.

Each Sunday through the month of September, I will post a description of the activities I coordinated and the resources I used to teach the environmental science merit badge. Today’s post is the third in the series.

Water Pollution – Oil Spill Activity

The Exxon Valdez oil spill occurred in Prince William Sound, Alaska, March 24, 1989, when an oil tanker bound for Long Beach, California, struck Prince William Sound’s Bligh Reef in the wee hours of ht morning and spilled over 10 million gallons of crude oil into the sea.

As the Scouts learned in the Environmental Science Timeline game we played the day prior, this disaster resulted in the International Maritime Organization introducing comprehensive marine pollution prevention rules through various conventions. We discussed this tragedy as I shared several photos and strategies that were used to clean up the oil.

We then engaged in an Oil Spill Experiment of our own. One Scout shared with us a video of an incredible new material – a foam material coated with oil-attracted silane molecules – that absorbs oil but not water. It was fascinating and extended our discussion.

Air Pollution – Acid Rain Activity

Acid rain is a broad term that includes any form of precipitation (rain, snow, fog, hail, or even dust) with acidic components, such as sulfuric or nitric acid that fall to the ground from the atmosphere in wet or dry forms. With the aid of the visual above, we discussed the pathway by which precipitation becomes acidic.

While we didn’t undertake the lab outlined below due to time constraints, I encouraged each of the Scouts to set up the lab portion of the activity is to demonstrate the effects of acid rain on our environment.

Materials

Six Petri dishes (3 for the control, 3 for the acidic solution you choose to test)
Pipette
Large bell jar or similar item
Sulfuric acid or an alternative acidic solution (lactic acid – milk or a citric acid – lemon juice)
Two 2-liter soft drink containers
Four small pieces of marble or limestone
Small growing plant
Four small pieces of raw meat (fish or chicken)
Two green leaves
Small amount of soil

Procedure

Several days in advance, prepare Petri dishes with soil & stone, leaf, and raw meat (two dishes each). One set is to be the control to which distilled water is added. Add a solution of 50% sulfuric acid to the other set. Keep these in a location that is secure so they don’t accidentally get spilled.

Display the Petri dishes and show the class how the acid has affected soil/stone, plant, and animal materials compared to the items in plain water. Together discuss what effects they think acid rain would have on the various aspects of their local ecosystem.

Set up the following long-term experiment:

Place the potted plant under the bell jar and add a Petri dish or other small vessel of 10% sulfuric acid. Maintain plant normally including acid solution.
Put about one inch of 10-15% sulfuric acid solution into one of the soft drink containers. Suspend a marble or limestone chip above the solution. Cap tightly.
Duplicate (a) and (b) with water only as controls.
Put a piece of raw meat in each of two Petri dishes; immerse one in water and cover, immerse the other in weak acid solution and cover. Note: these pieces of meat will
deteriorate but the effect of the acid solution will become evident over a period of time.

Excerpted from a slide show created by the Utah National Parks Council of the BSA

Pollution Prevention & Conservation

Lastly, we brainstormed a number of ways we could help to reduce pollution and conserve our natural resources. We filled the whiteboard with their ideas and discussed several in more depth.

Each Scout was then directed to choose two to put them into practice for the next couple of weeks. I asked that they keep track of their progress and to report back to me what they learned from the experience.

Join us next week for the final post in the series, whereupon I focus on an outdoor biodiversity study and an environmental impact statement.

Potions have always been essential in magic. Stories of witches tell of brewing magical drinks that turn men into mindless animals, restore youth, and make the drinker invisible. Other potions caused false emotion to be created such as when Ron Weasley declares his Love Potion-induced feelings for Romilda Vane.

“I don’t expect many of you to appreciate the subtle science and exact art that is potion-making… I can teach you how to bewitch the mind and ensnare the senses. I can tell you how to bottle fame, brew glory, and even put a stopper in death.” ~ Professor Severus Snape

First year students will learn many skills that will be important for potion making. Advanced students will apply these skills to the development of a Marauder’s map and wizard wands.

Science with Harry Potter: Potions @EvaVarga.net A wizard or witch who specializes in potion brewing is known as a potioneer or a potions master.

In this course, students are expected to keep a journal to record what has been done (including ingredients, procedures, spells, chants, etc) and reflect upon what was learned.

Print a periodic table of the elements and put it into your notebook. On the facing page sketch out elements 1-10, use color-coding for protons, neutrons, and electrons.

Potions

Knowledge of potions and charms is a powerful weapon against dark forces. Learn about ions, ionic and covalent bonds, and compounds. Write the definitions in your notebook.

Prepare each of the potions described below and record your observations. Illustrate as desired.

Potion 1: Goblin Slobber

Goblin slobber is a potion which is particularly effective against being followed through woods and caves. Just drip some goblin slobber on the path behind you and anything that is chasing you will be driven away.

One flask of water
¼ measure instant goblin slobber(dehydrated)
1 full measure Manticore milk
1 full measure water
3 drops goblin blood

Cauldron (mixing bowl will do if you have not yet received your cauldron)

1. Rehydrate the goblin slobber:Pour the instant goblin slobber into the flask of water. Stir briskly with wand to dissolve while chanting “soluloso aqualitem.” Repeat until fully dissolved.

2. Into the manticore milk pour the measure of water and the goblin blood and stir, repeating incantation.

3. The final step is to pour the two solutions into the cauldron and stir well chanting “goblinatum sloberosum.” You may need to adjust the quantities, so add them slowly.

Muggles will know these ingredients as: Instant goblin slobber= Borax. Manticore milk= Elmer’s glue. Goblin blood= green food coloring. flask=quart, measure=cup

Potion 2: Muggle Paper

This bright yellow potion gives you the ability to detect whether someone is muggle or magic.

1 vial nettle nectar
1/4 vial (approx) ground dragon scale
filter paper
Veritaserum

1. Put your filter paper into the cauldron.

2. Dissolve the ground dragon scale into the nettle nectar, shaking well to dissolve.

3. Pour over top of paper, allowing it to soak in well.

4. Remove paper from cauldron and hang to dry. Dust off any left over dragon scale.

5. Once paper is dry, dip right hand into Veritaserum (pour it into a bowl) and place directly onto paper with a slap.

6. Your true bloodline will be revealed!

Muggles will know these ingredients as: Nettle nectar= rubbing alcohol, ground dragon scale= turmeric, and veritaserum= baking soda and water solution.

Potion 3: Instant Ocean

This potion is very useful for creating a peaceful seaside vacation atmosphere in a small space. If made properly you can see the tiny waves and sea-foam inside the flask. This potion should be done in a place where messes are not a problem in case of sloppy magic by first year students. A calming charm may be needed in case of storms at sea.

Narrow-necked flask
2 vials Midsummer Dewdrops
1/2 dribble Kraken slime
3-4 drops of Squeaking-Squid ink
1 teaspoon Pulverized Narwhal Horn dissolved in ~2 tablespoons very warm water
Funnel
Large Cauldron

1. Stand flask in cauldron with funnel in top

2. Add 3-4 drops of squid ink to the Midsummer dew, shake well to mix

3. pour through the funnel into the flask

4. Add the Kraken slime to the mixture in the flask.

5. Pour the narwhal horn mixture into the bottle and remove the funnel.

Muggles will know these ingredients by their common names: hydrogen peroxide, dawn detergent (preferably green), blue food coloring, and yeast.

Marauder’s Map

In the film Harry Potter and the Prisoner of Azkaban, what first appears to be a blank piece of parchment becomes a magical Marauder’s Map. In this lesson, students create their own invisible inks, they learn what acids, bases and indicators are and how they can be used.

Begin by drawing a pH scale in your notebook. Use your “muggle” paper (created with Potion 2) to test a variety of substances around the house (vinegar, wine, lemon juice, baking soda, cola, bleach, ammonia, milk, etc). Make a table in your notebook showing your results. If you have litmus papers you can use them as well.

With your knowledge of acids and bases, create a map of your own using an ink you have devised.

Wizard Wands

Wands have been mentioned throughout time. Popular fantasy stories from a variety of origins have featured characters using wands. It could thereby be reasoned that Ollivander’s (makers of fine wands since 382 B.C.) had provided them.

To begin, learn about molecules and sketch several in your notebook (water, carbon dioxide, methane, glucose, etc.) Consider making models with gum drops or balls of clay and toothpicks.

“There will be no foolish wand-waving or silly incantations in this class. ” ~ Professor Snape on Potions class

Explosive Enterprises is a line of fireworks sold at Weasleys’ Wizard Wheezes. This group of fireworks included the original Weasleys’ Wildfire Whiz-Bangs as well as a variety of new and creative pyrotechnic products created by Fred Weasley and his twin brother George.

This post is part of a five-day hopscotch. Join me each day this week as we dive into each course.

Herbology (Botany)

Care of Magical Creatures (Zoology)

Potions (Chemistry) – this post

Alchemy Astronomy & Divination (Geology)

Magical Motion (Physics)

In September, we spent a few days in New York City on the island of Manhattan, the city’s historical birthplace and the economic and center. The borough contains several smaller islands including Liberty Island, Ellis Island (shared with New Jersey), Governors Island, and a few others. We were really looking forward to exploring the area and learning more about the history of the area, specifically the Statue of Liberty.

We arrived in Manhattan via Amtrak train from Boston in the early afternoon. We thereby opted to take in the Statue of Liberty and Ellis Island the following day when we could arrive early and board the first cruise boat. This turned out to be a wise decision as the queue upon our return to the main island was very long.

We grabbed a quick bite at the deli just outside the Courtyard Marriott on 40th where we are staying then hopped the green line express to Bowling Green. Here, we walked the short distance to the boarding area.

We immediately made our way to the National Park Visitor Center after we disembarked. Here we stamped our Park Passport Books and inquired about guided tours. We were in luck in that the first tour would begin in just 20 minutes. We took a few candid photos (Geneva pulled out her sketch book) as we waited.

As we planned to spend all our time in this area, we opted to purchase the New York CityPASS as the majority of the attractions were in this general area. In addition to Statue of Liberty and Ellis Island cruise, the pass provided us with tickets to each of the following attractions:

Statue of Liberty & Ellis Island
The Empire State Building
American Museum of Natural History
The Metropolitan Museum of Art
Guggenheim Museum
9/11 Memorial & Museum

Visiting the Statue of Liberty & Liberty Island

Liberty Island Tour

The group that gathered for the guided tour of Liberty Island was small and thereby very intimate. I am surprised more people don’t take advantage of this opportunity – they are so very informative and best of all, FREE!

As we listened to the park ranger, we learned the idea of gifting the United States with a monument was first proposed in 1865 by Frenchman Edouard de Laboulaye. Sculptor Frederic Auguste Bartholdi was commissioned to design a sculpture ten years later, with a goal of completing the work in 1876 to commemorate the centennial of the American Declaration of Independence.

As a joint venture between the two nations, it was agreed that the American people were to build the pedestal (carved in granite, the pedestal was designed by architect Richard Morris Hunt in 1884), and the French people were responsible for the Statue and its assembly here in the United States.

In France, public fees, various forms of entertainment, and a lottery were among the methods used to raise funds for the project. In the United States, theatrical events, art exhibitions, auctions and prizefights assisted in financing the construction.

Poet Emma Lazarus wrote her famous sonnet “The New Colossus” in 1883 for the art and literary auction to raise funds for the Statue’s pedestal.

Not like the brazen giant of Greek fame,

With conquering limbs astride from land to land;

Here at our sea-washed, sunset gates shall stand

A mighty woman with a torch, whose flame

Is the imprisoned lightning, and her name

Mother of Exiles. From her beacon-hand

Glows world-wide welcome; her mild eyes command

The air-bridged harbor that twin cities frame.

“Keep, ancient lands, your storied pomp!” cries she

With silent lips. “Give me your tired, your poor,

Your huddled masses yearning to breathe free,

The wretched refuse of your teeming shore.

Send these, the homeless, tempest-tost to me,

I lift my lamp beside the golden door!”

– Emma Lazarus

Centennial Gift 10 Years Late

Financing for the pedestal was completed in August 1885, and pedestal construction was finished in April 1886. The Statue was completed in France in July 1884 and arrived in New York Harbor in June 1885 onboard the French frigate “Isere.”

In transit, the Statue was reduced to 350 individual pieces and packed in 214 crates. The Statue was reassembled on her new pedestal in four months’ time. On October 28, 1886, President Grover Cleveland oversaw the dedication of the Statue of Liberty in front of thousands of spectators.

Homage to the Statue of Liberty Supporters

On Liberty Island, there are several small sculptures commemorating several of the key supporters of the Statue of Liberty gift. I really enjoyed hearing the personal triumphs that made it all possible.

Edouard de Laboulaye ~ The “Father of the Statue of Liberty.” He provided the idea that would become the Statue.
Frederic Auguste Bartholdi ~ The French artist and sculptor who designed the Statue of Liberty Enlightening the World.
Alexandre-Gustave Eiffel ~ The architect and engineer who designed the Statue’s internal support.
Emma Lazarus ~ The poetess who wrote “The New Colossus” to help raise money for the pedestal’s construction.
Joseph Pulitzer ~ The newspaper publisher who helped raise the money needed to complete the pedestal’s construction.

One of the things I overheard many of the young visitors ask as we walked about the island was, “Why is it green?” I knew that when I returned home, this was a concept I wanted to revisit with my children.

Bring it Home ~ Oxidation Reduction Reactions

Why is the Statue of Liberty Blue-Green?

Begin by showing students photographs of the Statue of Liberty. Ask students to describe the color. Students usually give the right answer: that it is blue or aquamarine (blue-green). Now ask them why it is this color. Students generally have no clue.

Explain that the color is due to the oxidation of copper. Next, show them a piece of rusted metal and point out that the red color of rust is caused by the oxidation of iron.

Oxidation Explained with Chemical Equations

Chemical reactions can be divided into two classes: redox (reduction-oxidation) reactions and non-redox reactions based on whether electron transfer process is involved or not. A redox reaction consists of two half reactions: a reductive half in which a reactant accepts electrons and an oxidative half in which a reactant donates electrons.

2Cu + O2 → Cu2O

The nature of a redox reaction is that one reactant donates its electrons to the other reagent. For example, in the oxidation of copper by oxygen, copper atoms donate electrons to an oxygen molecule so copper is oxidized while oxygen is reduced.

The Statue of Liberty gets its blue-green color from patina formed on its copper surface mainly through oxidation along with several other chemical reactions. The main constituent of patina contains a mixture of 3 compounds: Cu4SO4(OH)6 in green; Cu2CO3(OH)2 in green; and Cu3(CO3)2(OH)2 in blue. The following reactions are involved.

2Cu2O + O2 → 4CuO

Cu + S → 4CuS

The oxidation starts with the formation of copper oxide (Cu2O), which is red or pink in color (equation 1), when copper atoms initially react with oxygen molecules in the air. Copper oxide is further oxidized to copper oxide (CuO), which is black in color (equation 2). In the 19th and early 20th century, coal was the major fuel source for American industry and it usually contains sulfur. Thus, the black copper sulfide (CuS) also forms (equation 3).

2CuO + CO2 + H2O → Cu2CO3(OH)2

3CuO + 2CO2 + H2O → Cu3(CO3)2(OH)2

4CuO + SO3 +3H2O → Cu4SO4(OH)6

Over the years, CuO and CuS slowly reacts with carbon dioxide (CO2) and hydroxide ions (OH-) in water from the air to eventually form Cu2CO3(OH)2 (equation 4) , Cu3(CO3)2(OH)2 (equation 5) and Cu4SO4(OH)6 (equation 6), which constitute the patina. The extent of humidity and the level of sulfur-related air pollution have a significant impact on how fast the patina develops, as well as the relative ratio of the three components.

Take it Further

Can you think of another oxidation reduction reaction? Write out the chemical equations to further describe this process.

In brilliant collaboration, Carl and Gerty Cori studied how the body metabolizes glucose and advanced the understanding of how the body produces and stores energy. Their findings were particularly useful in the development of treatments for diabetes. They were awarded the Noble Prize for their discovery of how glycogen (animal starch) – a derivative of glucose – is broken down and resynthesized in the body, for use as a store and source of energy.

The pair were interested in how the body utilizes energy. The couple spent more than three decades exploring how the human body metabolizes glucose. It was known in the 1920s that faulty sugar metabolism could lead to diabetes, and it was also known that insulin kept the disease in check.

The effect of insulin on blood sugar levels had been observed, but scientists did not understand the biochemical mechanism behind insulin’s effect or how carbohydrates were metabolized. In 1929, the couple described what is now known as the Cori cycle; an important part of metabolism. To put it simply, lactic acid forms when we use our muscles, which is then converted into glycogen in the liver. Glycogen, in turn, is converted into glucose, which is absorbed by muscle cells.

The Cori Cycle

The Cori Cycle refers to the metabolic pathway in which lactate produced by anaerobic glycolysis in the muscles moves via the blood stream to the liver where it it is converted to blood glucose and glycogen. High intensity exercise will mostly get it’s energy or ATP from the pathway of the glycolitic system. Less intense activity will receive its energy or ATP from the aerobic pathway utilizing the Krebs cycle.

When utilizing the glycolitic system, cycle after cycle, lactate will start to build up. Lactate from the glycolitic system will diffuse from the muscles into the bloodstream. It will then be transported into the liver. In the liver it is converted from lactate back to pyruvate back to glucose, which is then available to the muscles again for energy, this is called gluconeogenesis. The whole process is called the Cori Cycle.

The more you train with high intensity exercise, the more capable the enzymes and transporters become that are needed for the Cori Cycle. Your liver gets better at using the lactate, not more efficient (it still needs the same amount of ATP to run the Cori Cycle) but it will do the cycle faster.

Gerty Cori Biography

Gerty Radnitz was born in Prague in what was then Austria-Hungary. She received her PhD in medicine from the German University of Prague’s Medical School in 1920. It was here that she met fellow classmate, Carl Ferdinand Cori, whom she married later that same year.

The couple moved to Buffalo, New York in 1922 and began researching metabolic mechanisms. As a woman, Gerty Cori was employed on much less favorable terms than her husband and encountered other forms of gender discrimination throughout her career.

The couple moved to Washington University in St. Louis in 1931 after both were offered positions there. When the Coris were hired at Washington University, she received one-tenth Carl’s salary, even though they were equal partners in the laboratory.

Gerty and her husband continued to investigate how glycogen is broken down into glucose and in 1939 were able to both identify the enzyme that initiates the decomposition and also to use the process to create glycogen in a test tube.

She became full professor in 1947, the same year that she and Carl were awarded the Nobel Prize “for their discovery of the course of the catalytic conversion of glycogen.” She was the first American woman to win the Nobel Prize in Science.

Around this time Gerty was diagnosed with myelosclerosis, a disease of the bone marrow. She died in 1957 at the age of 61.

Bring it Home

Try this hands-on lab from Amy Brown Science to discover The Use of Glucose in Cellular Respiration

Enjoy the Carl and Gerty Cori and Carbohydrate Metabolism commemorative booklet produced by the National Historic Chemical Landmarks program of the American Chemical Society in 2004.

Read about the dip-and-read test strips developed by Helen Free and her husband, Al. Originally designed to test for glucose in urine, the test strips were such an advance that researchers have since combined 10 urine tests to check for ailments like liver failure, urinary tract infections, and others—onto one plastic stick.

Learn more about our digestive system with these hands-on enzyme labs.

Investigate What Types of Food Contain Starch and Protein?

Building Macromolecule is a paper-scissors-tape activity used to help students envision the process of synthesis, building macromolecules out of smaller subunits.

Visit my Science Milestones page to learn more about scientists whose discoveries and advancements have made a significant difference in our lives or who have advanced our understanding of the world around us.

Interested in learning about others who were born in the month of August? Hop over to Birthday Lessons in August to read posts by other iHomeschool Network bloggers.

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