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Strontium

physical science Maturity 7-9

Some things make a bright red fire.

Ignis Brunensis 2010-05-22 (5).jpg
Ignis Brunensis 2010-05-22 (5).jpg
This is from a special metal. It helps fireworks look pretty. It also helps make flares. It is found in rocks.
Celestine Poland.jpg
Celestine Poland.jpg
Do you like red colors?

39 words

Strontium is a silver metal.

Strontium 1.jpg
Strontium 1.jpg
It is very soft. It can change color in the air. It is found in rocks.
Celestine Poland.jpg
Celestine Poland.jpg
One rock is called celestine. This metal can make a bright red flame.
FlammenfärbungSr.png
FlammenfärbungSr.png
People use it to make red fireworks. It can also make bright flares. This metal is quite special.

57 words

Strontium is a soft, silver-white metal.

Strontium 1.jpg
Strontium 1.jpg
It is very reactive. This means it changes quickly when it touches air or water. It can even catch fire if it is a fine powder.

Strontium was first found in 1790. Two men found it in a village in Scotland. They named it after that village, Strontian.

Celestine Poland.jpg
Celestine Poland.jpg
In nature, strontium is usually found inside minerals. One common mineral is called celestine.

This metal can do many things. If you put strontium salts in a flame, the flame turns bright red.

FlammenfärbungSr.png
FlammenfärbungSr.png
People use this trick to make red fireworks and flares.
Ignis Brunensis 2010-05-22 (5).jpg
Ignis Brunensis 2010-05-22 (5).jpg
In the past, much strontium was used to make glass for old TVs.

Some types of strontium are special. Most natural strontium is stable and safe. However, a man-made version called strontium-90 is radioactive. This can be dangerous. It can get into bones because the body thinks it is calcium. This can cause health problems like cancer.

163 words

Strontium is a soft, silver-white metal with a pale yellow tint.

Strontium 1.jpg
Strontium 1.jpg
It is an alkaline earth metal, which means it belongs to a specific group of elements. This metal is highly reactive, so it changes quickly when it touches things. For example, it forms a dark oxide layer when it is exposed to air. If the metal is in a very fine powder, it can even catch fire on its own.
Strontium 1.jpg
Strontium 1.jpg
This reactivity is why strontium is rarely found alone in nature. Instead, it is usually found inside minerals like celestine or strontianite.

Because it is so reactive, strontium works in specific ways. When it touches water, it reacts to produce strontium hydroxide and hydrogen gas. It can also burn in the air to create strontium oxide and strontium nitride.

FlammenfärbungSr.png
FlammenfärbungSr.png
If you use strontium salts in a flame, the fire turns a bright crimson-red.
FlammenfärbungSr.png
FlammenfärbungSr.png
This special color is very useful for making red fireworks and flares.
Ignis Brunensis 2010-05-22 (5).jpg
Ignis Brunensis 2010-05-22 (5).jpg
Scientists also use it in a process called electrolysis to separate the metal. This involves using electricity to break apart a mixture of chemicals.

The story of strontium began in a small Scottish village named Strontian.

Celestine Poland.jpg
Celestine Poland.jpg
In 1790, Adair Crawford and William Cruickshank discovered a new mineral there. They noticed the ore had different properties than other minerals they knew. Later, a professor named Thomas Charles Hope suggested the name strontites. In 1808, the scientist Humphry Davy successfully isolated the metal using electrolysis.
Celestine Poland.jpg
Celestine Poland.jpg
He decided to call the new element strontium. This name honors the place where the discovery first happened.

Strontium has many different uses and interesting facts. In the 19th century, it was used to help produce sugar from sugar beets.

Monitor.arp.jpg
Monitor.arp.jpg
During the time when many people used cathode-ray tube televisions, strontium was very important. About 75% of the strontium used in the United States went into making the glass for those TV screens.
Monitor.arp.jpg
Monitor.arp.jpg
Most natural strontium is the stable isotope called strontium-88. It makes up about 82.6% of all natural strontium found on Earth. This element is the 15th most abundant element in the Earth's crust.

It is helpful to think of strontium as a cousin to calcium. Because they are so similar, the human body treats them in a similar way. This similarity can be helpful or dangerous. For instance, a man-made version called strontium-90 is radioactive.

Soviet RTG.jpg
Soviet RTG.jpg
Because the body thinks it is calcium, it can absorb strontium-90 into the bones. This can lead to serious health problems like leukemia or bone cancer.
Soviet RTG.jpg
Soviet RTG.jpg
While natural strontium is safe at low levels, this radioactive version must be handled with great care.

450 words

Strontium is a chemical element with the symbol Sr and the atomic number 38. It belongs to a group called the alkaline earth metals. This element is a soft, silver-white metal with a pale yellow tint.

Strontium 1.jpg
Strontium 1.jpg
Strontium is highly chemically reactive, meaning it changes easily when it touches other substances. Because of this reactivity, it does not stay pure in nature. Instead, it is always found combined with other elements in minerals. It is the 15th most abundant element in the Earth's crust.
Celestine Poland.jpg
Celestine Poland.jpg

In the natural world, strontium is mostly found in two minerals. The first is celestine, which is a sulfate mineral. The second is strontianite, which is a carbonate mineral.

Celestine Poland.jpg
Celestine Poland.jpg
Because strontium reacts so quickly with oxygen and water, it only exists in these combined forms. When the metal is exposed to air, it forms a dark oxide layer. If the metal is in a very fine powder, it becomes pyrophoric. This means it can ignite spontaneously just by touching the air at room temperature. To keep it safe, scientists store the metal under liquids like mineral oil or kerosene.

Strontium has physical properties that sit between its neighbors, calcium and barium. It is softer than calcium but harder than barium. Its melting point is 777 °C, which is lower than calcium's 842 °C. Its boiling point is 1377 °C, also lower than calcium's 1484 °C. The density of strontium is 2.64 g/cm3. This value is intermediate between calcium at 1.54 g/cm3 and barium at 3.594 g/cm3.

Strontium 1.jpg
Strontium 1.jpg
These similarities make it useful for many chemical processes.

The history of strontium began in the village of Strontian, Scotland. In 1790, Adair Crawford and William Cruickshank discovered ores there that behaved differently than other minerals. Later, a professor named Thomas Charles Hope proposed the name "strontites" to honor the location. In 1808, the scientist Humphry Davy finally isolated the metal. He used a process called electrolysis, which uses electricity to break down chemical mixtures. Davy eventually settled on the name strontium for the element.

Celestine Poland.jpg
Celestine Poland.jpg

Strontium has been used in many different industries over time. During the 19th century, it was vital for making sugar from sugar beets. The German sugar industry used the "strontian process" for a long time. Before the digital age, strontium was used heavily in electronics. At the peak of cathode-ray tube television production, 75% of strontium used in the United States went into making faceplate glass.

Monitor.arp.jpg
Monitor.arp.jpg
As television technology changed, the demand for strontium in this area declined significantly.

One of the most famous uses of strontium is in pyrotechnics. When strontium salts are burned, they produce a bright, crimson-red flame.

FlammenfärbungSr.png
FlammenfärbungSr.png
This effect is used to make red colors in fireworks and flares.
Ignis Brunensis 2010-05-22 (5).jpg
Ignis Brunensis 2010-05-22 (5).jpg
Scientists also study its isotopes, which are different versions of the same element. Most natural strontium is the stable isotope strontium-88, making up about 82.6% of all natural strontium. Other isotopes, like strontium-87, help scientists with rubidium–strontium dating to find the age of materials.

However, some versions of strontium can be dangerous. The synthetic isotope strontium-90 is radioactive and is produced during nuclear fission.

Soviet RTG.jpg
Soviet RTG.jpg
Because strontium is chemically similar to calcium, the human body absorbs it in a similar way. If a person absorbs strontium-90, it can settle in the bones. This can lead to serious health issues like leukemia or bone cancer. The 1986 Chernobyl accident released a large amount of this isotope into the environment.
Soviet RTG.jpg
Soviet RTG.jpg
Understanding these connections between chemistry and biology is essential for safety.

595 words
🖼️ Images & Media (6)
File:Strontium 1.jpg
Strontium 1.jpg
File:FlammenfärbungSr.png
FlammenfärbungSr.png
File:Celestine Poland.jpg
Celestine Poland.jpg
File:Monitor.arp.jpg
Monitor.arp.jpg
File:Ignis Brunensis 2010-05-22 (5).jpg
Ignis Brunensis 2010-05-22 (5).jpg
File:Soviet RTG.jpg
Soviet RTG.jpg
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