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Ionization

physical science Maturity 11-13 Next article →

Everything in our world is made of tiny building blocks called atoms. Usually, these atoms are neutral, meaning they have no electrical charge. Ionization is the name for the way an atom or molecule gains a charge. This happens when an atom either gains or loses electrons. Electrons are tiny parts that orbit the center of an atom. When an atom changes this way, it becomes something called an ion.

First Ionization Energy blocks
First Ionization Energy blocks

These ions are very important because they carry electrical energy.

There are many ways this change can happen. One way is through collisions. An atom might bump into another atom or a tiny particle like a proton. These bumps can knock an electron loose. Another way is through electromagnetic radiation, which is a fancy word for light. If the light has enough energy, it can push an electron away. Sometimes, this creates a chain reaction called an avalanche.

Electron avalanche
Electron avalanche

In an electric field, one electron hits an atom and releases more electrons. These new electrons then hit even more atoms, creating a huge rush of ions.

Scientists have studied these tiny collisions for a long time. One famous way to look at this is through the Bohr model of the atom. This model helps explain how light can cause ionization. There is also a special kind of ionization called tunnel ionization. In this version, an electron does not go over a barrier. Instead, it goes through the barrier like a ghost walking through a wall.

Tunnel ionization 3
Tunnel ionization 3

This happens because of the wave nature of electrons. A scientist named Keldysh even created a model to describe this process in 1934.

Different atoms need different amounts of power to change. This amount of power is called ionization energy. Some atoms hold onto their electrons very tightly. Others let them go quite easily. We can see patterns in these energies using Mendeleev's table.

First Ionization Energy blocks
First Ionization Energy blocks

For example, there is a big drop in energy after rare gas atoms. This tells scientists that a new shell of electrons is forming. Measuring these energies helps us understand how all the elements in the universe are organized.

We see ionization happening in many places every day. You can see it in the glowing gas inside a fluorescent lamp. It is also used in medical tools like radiation therapy to treat people. Even the sky shows us ionization. When solar wind hits the Earth, it can create beautiful auroras.

Aurora in Abisko near Torneträsk
Aurora in Abisko near Torneträsk

These colorful lights happen because particles in the atmosphere become ionized. It is a giant, natural display of science happening right above our heads.

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🖼️ Images & Media (6)
File:Aurora in Abisko near Torneträsk.jpg
Aurora in Abisko near Torneträsk.jpg
File:Electron avalanche.gif
Electron avalanche.gif
File:First Ionization Energy blocks.svg
First Ionization Energy blocks.svg
File:Tunnel ionization 3.png
Tunnel ionization 3.png
File:Lambda type population trapping.svg
Lambda type population trapping.svg
File:Kuchiev's model.png
Kuchiev's model.png
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