Lanthanum

Lanthanum is a soft, silvery metal.

It looks like shiny silver. It can change color in the air. This happens because it reacts with the air.

A man named Carl Mosander found it. He found it hidden inside other things. This is why it has a special name. It means "to lie hidden."

This metal is not very rare. It is found in the ground.

It is often found with other metals. People must work hard to get it.

We use it for many things. It helps make bright lights. It is also used in lighters.

It can even help people with kidney problems.

It is a very useful metal. Do you want to learn more?

Lanthanum is a soft, silvery-white metal.

It is part of a group called lanthanides. These are 15 similar elements in the periodic table. Lanthanum is the first one in this group.

A chemist named Carl Gustaf Mosander found it in 1839. He found it hidden inside cerium. Because it was hard to find, he gave it a Greek name. It means "to lie hidden."

Even though it is called a "rare-earth" metal, it is not very rare. It is the 28th most common element in the Earth's crust. It is almost three times as common as lead.

It is often found in minerals like monazite. Getting pure metal from these rocks is a hard job. It took until 1923 to make pure lanthanum.

We use this metal in many ways. It can be used in lighters and studio lights.

It is also used as a medicine. Lanthanum carbonate helps treat people with kidney failure. It helps bind phosphate in their blood.

Lanthanum is a silvery-white metal that is soft and easy to shape.

It is the very first element in a group called the lanthanides. This group contains 15 similar elements found in the periodic table. Scientists often call lanthanum a rare-earth element. This name might sound like it is hard to find. However, it is actually the 28th most common element in the Earth's crust. It is almost three times as common as lead.

This metal works in many interesting ways through its chemistry. Most of the time, a lanthanum atom gives up three electrons. This happens because it wants to reach a stable state. When it does this, it forms what scientists call a +3 oxidation state. Lanthanum is also very reactive when it touches the air. It can tarnish or turn dark after just a few hours. If you had a piece of metal one centimeter wide, it could corrode completely in one year.

A Swedish chemist named Carl Gustaf Mosander discovered lanthanum in 1839. He found it while studying cerium nitrate. He realized that the cerium was actually a mixture of different oxides. He separated them and found two new ones. He named one of them lanthana. The name comes from an ancient Greek word. It means "to lie hidden." This was a perfect name because the element was hiding inside another one.

Finding pure lanthanum was a very hard job for scientists. It is often found in minerals like monazite and bastnäsite. These minerals contain a mix of many different rare-earth elements. Because the elements are so similar, separating them is quite difficult. It took a long time to figure out the right way to do it. Pure lanthanum metal was not isolated until 1923.

We use lanthanum in many things you might see every day. It can be used in the parts of lighters that create a spark. It is also used in studio lights and projectors. Some special glass uses lanthanum as an additive. In medicine, it has a very important job. A compound called lanthanum carbonate is used to treat kidney failure. It works by acting as a phosphate binder in the blood.

Lanthanum is a chemical element with the symbol La and atomic number 57. It is a soft, silvery-white metal that is quite ductile, meaning it can be easily shaped.

As the first element in the lanthanide series, it serves as the prototype for a group of 15 similar elements. While it is classified as a rare-earth element, it is not actually rare in the Earth's crust. It is the 28th most abundant element, making it nearly three times as common as lead. This element is vital for many technologies, ranging from specialized glass to medical treatments.

At the atomic level, lanthanum has a specific way of behaving during chemical reactions. A single lanthanum atom has 57 electrons arranged in a specific configuration. It has three valence electrons located in the 5d and 6s subshells. In most chemical reactions, the atom gives up these three electrons. This process creates a +3 oxidation state, which allows the atom to reach a stable configuration similar to the noble gas xenon. While some lanthanum(II) compounds exist, they are much less stable than the +3 state.

The physical properties of lanthanum are shaped by its unique electron structure. Unlike many other lanthanides, a single lanthanum atom in a gas phase has no 4f electrons. This makes it only weakly paramagnetic, which means it is not strongly attracted to magnetic fields. However, its 4f shell can become partially occupied in certain chemical environments. This allows the electrons to participate in chemical bonding. This characteristic is why lanthanum is placed in the f-block of the periodic table. It also has a relatively low melting point of 920 °C compared to other trivalent lanthanides.

Lanthanum is highly reactive, especially when it meets the air or water. It is the most reactive element among the lanthanide series. When exposed to air, it tarnishes quickly and can turn completely dark in just a few hours. If you had a sample only one centimeter in size, it could corrode entirely within a single year. This happens because the oxide that forms does not create a protective coating. Instead, it flakes off like rust on iron. When lanthanum reacts with water, it produces lanthanum(III) hydroxide and releases a lot of heat, often accompanied by a hissing sound.

The history of lanthanum is a story of uncovering what was hidden. In 1839, the Swedish chemist Carl Gustaf Mosander discovered the element. He was studying cerium nitrate and realized it was actually a mixture of different oxides. By roasting the sample in air and treating it with nitric acid, he separated the new oxides. He named the substance lanthana, which comes from the Greek word meaning "to lie hidden."

It took many more years of complex work to isolate the pure metal. Scientists did not successfully isolate pure lanthanum metal until 1923.

Extracting lanthanum is a difficult and expensive process because it is usually found mixed with other elements. It often occurs alongside cerium in minerals like monazite and bastnäsite.

In these minerals, lanthanum typically makes up about one-quarter of the total lanthanide content. Because the different rare-earth elements are so chemically similar, separating them requires very complex methods. This difficulty is part of why the term "rare-earth" is still used, even though the element is relatively abundant in the crust.

Today, lanthanum is used in a wide variety of important industrial and medical roles. It is used as a catalyst and as an additive in glass to change its properties. You might find it in carbon arc lamps for projectors or as an ignition element in lighters and torches.

It is also used in gas tungsten arc welding electrodes and as electron cathodes. In the field of medicine, lanthanum carbonate serves a critical purpose. It acts as a phosphate binder for patients experiencing kidney failure, helping to manage high phosphate levels in the blood.

Finally, we can look at the very building blocks of the element through its isotopes. Naturally occurring lanthanum is made of two isotopes: La-139 and La-135. The La-139 isotope is by far the most common, making up 99.911% of all natural lanthanum. It is created in stars through processes called the s-process and the r-process.

The other isotope, La-135, is a very rare primordial radioisotope. Most other versions of lanthanum are synthetic, meaning they are created by humans in a laboratory.