By Emily Newton 
We use different types of metal every single day, from the frame of our cars to the silverware we typically use to eat lunch. Many of these metals fall into different families on the periodic table. Today, we’ll be talking about alkaline earth metals. What are alkaline earth metals, and where might you encounter them in your daily life?
First, what are alkaline earth metals?
Late in the 18th century, any substance that could not be dissolved in water and did not burn or melt in regular fire was referred to as an ‘earth.’ From there, they were classified by their resemblance to other known materials. Alkaline earth metals had a striking resemblance to other known alkalis, such as soda ash or potash, so they were classified as such.
Later, it was discovered that the elements being classified as alkaline earth metals were actually oxides of those metals — the metal atoms were combining with oxygen.
The alkaline earth metals, in order of abundance, are:
| Some Degree of Commerical Use | No Commerial Use |
|---|---|
| Calcium | Radium |
| Magnesium | |
| Barium | |
| Strontium | |
| Beryllium |
Calcium is the fifth most abundant element in the Earth’s crust, coming in behind magnesium, silicon, iron, and aluminum.
What sets alkaline earth metals apart from other metals on the periodic table?
First, though classified as metals, these elements are fairly soft and malleable. They have lower melting and boiling points than other metals but are still strong when compared to other, similar elements. The earth metals are also highly reactive in their pure state, which is why they are not usually found in this state in nature.
These earth metals also burn in a variety of different colors. Calcium and radium both burn red, while beryllium and magnesium burn white and barium burns a bright green.
Alkaline earth metals are also great conductors of electricity.
In the future, if element 120 is added to the periodic table, it will most likely be a new form of alkaline earth metal.
Where do you think you encounter alkaline earth metals in daily life? These alkaline earth metal examples might surprise you. We’ll start with the most abundant element — calcium.
Researchers didn’t isolate calcium until 1808, even though it’s the 5th most abundant element on the planet. Calcium gets its name from the Latin word calx, which means lime. It loves reacting with water and oxygen, so you’ll never find pure elemental calcium in nature. That isn’t necessarily a bad thing, however.
Most of us are familiar with calcium’s chemical compounds. It is a critical part of human health because of how many parts of the body it influences. Calcium in the blood notifies the body to regulate hormones, contract muscles and send nerve signals. What else is it good for?
Scientists first isolated elemental magnesium in 1831. Its name comes from Magnesia, a district in Greece that housed large concentrations of this alkaline earth metal. Today, most of the magnesium you see in supplements or other applications comes from the oceans. A cubic kilometer of seawater contains roughly 1.3 billion kilograms of magnesium.
As people’s health awareness increases, the importance of magnesium is permeating public awareness. It is a highly influential supplement, impacting everything from sleep to heart rate. In a nonmedical situation, magnesium is an enticing option for consumer technologies because it isn’t as heavy as other alternatives. It makes it perfect for constructing a small phone or laptop.
Barium dates back to 1808, but it’s another element that loves to react with oxygen and water. If you ever find it in nature, it’s usually in the form of barium oxide or barium hydroxide. Barium gets its name from the Greek barys, which means heavy. It’s not an element you generally want to encounter in your daily life — barium compounds are toxic to human beings.
This doesn’t mean this alkaline earth metal has no applications. However, they tend to be more niche whereas elements like calcium and magnesium are more present in society.
Strontium dates back even further than some of the other elements on our list. Scientists first discovered it in 1790 — mostly by accident. Adair Crawford was mixing the element witherite with hydrochloric acid. Instead of getting the results he wanted, he accidentally discovered strontium. It doesn’t exist in its pure form in nature, and today mostly comes from celestite and strontianite.
While it is not a field using strontium in a commercial way, anthropologists want to keep an eye out for it during their research. If they find bones or teeth during excavations, they can measure the amount of strontium ions present to discover the specimen’s origins. This works for humans and animals, unlocking the secrets to ancient pasts.
Beryllium gets its name from the element beryl, where it occurs naturally. Scientists were trying to figure out what element they saw in both beryl and emeralds, and eventually, they found beryllium. Some chemists used to call it glucinum, meaning “sweet,” because beryllium and some of its compounds have a sweet taste. Spoiler alert — don’t try this. Beryllium is poisonous.
Beryllium has non-magnetic properties, is extremely dense and has very little give in its movement. This is why it is so good for making alloys and heavy-duty equipment.
Marie Curie, one of the most famous chemists of all time, discovered radium in 1898 along with polonium. She extracted uranium from a material called pitchblende. She found that it was more radioactive after she removed the uranium, which led to the discovery of radium and polonium. Radium is so radioactive that the lab notes Marie Curie took are still too contaminated to handle without protective gear. Hopefully, you’ll never come into contact with radium.
The element has a storied and controversial past. It was inappropriately used for medical applications in the early 1900s to treat mental health conditions and rheumatism. This has since been debunked with more effective treatments that didn’t cause additional damage.
Where have you encountered alkaline earth metals in your daily life? Hopefully, radium wasn’t one of the ones you encountered, but many of the others help to subtly shape our lives in ways that most of us don’t even think about. It’s possible the applications may expand beyond our imagination one day as researchers continue innovating.
The next time you hop on a flight, think about the magnesium in the airplane parts or the calcium in the glass of milk the flight attendant hands you. Alkaline earth metals are all around us — you just have to know where to look.
This site uses Akismet to reduce spam. Learn how your comment data is processed.