From autumn leaves to watercolor paints, all of the colors around you are visual chemistry. Colors are seen within the Visible Light wavelength range of energy, and we break down the basics in one of our newest explanations in our Chemistry section on Expii.com. Here’s the TL;DR:
The colors in fireworks can be traced back to the movement of electrons in chemical compounds!
If you celebrate America’s Independence Day, there’s a good chance that you and your family have already made plans to witness this amazing chemical phenomenon as part of a loud and colorful national tradition.
Here are six of the colors you’re most likely to see this Fourth of July:
Red: Strontium Ions
- Naturally occurring strontium is a mixture of its four stable isotopes.
- In nature, strontium exists in the shells of some deep ocean organisms.
- The most accurate atomic clock to date was created from strontium atoms.
- One of strontium’s isotopes, 90Sr, is radioactive. Its radioactive properties are used in cancer therapy, and potentially in the generation of electricity for space vehicles and remote weather stations.
White: Magnesium and other non-ionized metals
- Magnesium tastes sour. Small amounts of magnesium in mineral water gives it that slightly sour flavor.
- Magnesium can be found in every cell in your body. It is the 11th most abundant element in the human body. About 60% of the magnesium in your body is found in the skeletal system.
- Magnesium was discovered in 1808 by Sir Humpry Davy, who wanted to call the element “magnium.”
Blue: Copper Ions
- The Statue of Liberty is made from 179,000 pounds of copper. That’s about 11 times as heavy as a Tyrannosaurus rex.
- Copper was the first metal to be molded by man, along with gold and meteoritic iron.
- Copper is a natural antibacterial agent, and the metal is toxic to invertebrates. Brass is an alloy of copper, so brass door handles are commonly used in public facilities to help prevent disease transmission.
- About 80% of the copper that has been mined to date is still in use. This is because copper is a 100% recyclable metal.
Orange: Calcium Ions
- Calcium exists in the human body as calcium ions; it can’t be found in its element form. It is the fifth most abundant element in our bodies.
- Your teeth and bones contain 99% of the calcium in your body.
- Before the invention of electricity, calcium oxide (known as lime) was burnt to produce bright lights for plays. That’s where the saying “in the lime-light” comes from.
Yellow: Sodium ions, just like the ones found in table salt
- Elemental sodium reacts violently when coming into contact with water.
- When we sweat, our bodies release sodium. If the body runs low on sodium, it can cause the muscles to cramp.
- Sodium plays a large role in maintaining a healthy fluid balance in the body’s cells.
- Many kinds of outdoor lighting like street lamps use sodium to produce light. These types of lamps give off yellow light, just like fireworks.
Green: Barium ions
- Barium is present in foods like carrots, onions, lettuce, and beans.
- Barium’s radioactive half-life is as much as one thousand times longer than the age of the Universe.
- Its name comes from the Greek word meaning “heavy.” (Probably because it’s so heavy.)
- The mineral barite contains lots of barium. Barite was part of ancient witchcraft because the stones glow after exposure to light.
How Do These Chemicals Make a Firework, a Firework?
Each of these compounds is added to a mixture of ingredients that experience an exothermic reaction when provided with the energy they need to begin their reaction. This allows fireworks to be sent up with just one spark that travels up to the part of the rocket containing the reactants as the firework gets to a safe height in the sky, at which point, the heat allows the chemicals to react and results in a colorful explosion of burning compounds in the sky.
Do you love watching fireworks? Let us know in the comments below!
To learn more about chemistry, check out our current work-in-progress topic, Chemistry, on our site!