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Deuterium

physical science Maturity 11-13 Next article →

Deuterium, also known as hydrogen-2 or heavy hydrogen, is a stable isotope of hydrogen.

Standard Model Deuterium
Standard Model Deuterium

While common hydrogen, called protium, consists of only a single proton, deuterium contains one proton and one neutron.

Standard Model Deuterium
Standard Model Deuterium

This extra neutron gives deuterium a mass of approximately 2 atomic mass units. This is about twice the mass of a standard protium atom. Because of this mass difference, deuterium behaves differently in chemical and physical processes. It is represented by the chemical symbol D or H. Scientists often use the symbol D to distinguish it from regular hydrogen during experiments.

Hydrogen deuterium glow comparison
Hydrogen deuterium glow comparison

The unique mass of the deuterium nucleus affects how its electrons behave. In quantum mechanics, the energy levels of electrons depend on the reduced mass of the atom.

Deuterium lamp 1
Deuterium lamp 1

Because the deuterium nucleus is heavier, the reduced mass of the system is slightly different than in protium. This change causes the wavelengths of light emitted by deuterium to be shorter. Specifically, the wavelengths are shorter by about 0.0272%. In astronomical observations, this difference appears as a blue Doppler shift. This shift is equivalent to a speed of 81.6 kilometers per second. These differences are even more noticeable in vibrational and rotational spectroscopy.

Deuterium lamp 1
Deuterium lamp 1

Most deuterium in the universe was created during the Big Bang 13.8 billion years ago. During the early universe, a period known as the deuterium bottleneck occurred. At first, the universe was too hot for deuterium to stay together. Any deuterium that formed was immediately destroyed by high energy levels. Once the universe cooled to a specific temperature, a sudden burst of element formation happened. This allowed deuterium to form, which then fused into helium. This process helped set the ratio of elements in the early universe.

Standard Model Deuterium
Standard Model Deuterium

Deuterium is a vital tool in modern science and industry. It is used in many nuclear weapons and fusion power experiments.

Ivy Mike Sausage device
Ivy Mike Sausage device

It also serves as an effective neutron moderator. A neutron moderator is a substance used to slow down neutrons in a nuclear reactor. Heavy water, which is water concentrated with deuterium, is used in many reactors. For example, India operates several pressurized heavy water plants.

Deuterium Ionized
Deuterium Ionized

Scientists also use deuterium as an isotopic label in biogeochemistry and NMR spectroscopy. In NMR spectroscopy, deuterium has a much lower frequency than protium.

Deuterium Ionized
Deuterium Ionized

This allows researchers to use deuterated solvents to prevent signals from overlapping.

American chemist Harold Urey discovered deuterium in 1931.

Urey
Urey

He and other researchers worked to produce samples of heavy water. This achievement was so significant that Urey won the Nobel Prize in 1934. His work opened new doors for understanding the composition of matter. Today, the study of deuterium continues to help us understand the history of our solar system.

Astronomers use the ratio of deuterium to hydrogen to study space.

Standard Model Deuterium
Standard Model Deuterium

Gas giant planets like Jupiter show a primordial ratio of about 26 deuterium nuclei per 10 hydrogen nuclei.

Deuterium Ionized
Deuterium Ionized

Comets often show much higher ratios, similar to Earth's oceans. For example, Comet 103P/Hartley has a ratio nearly identical to Earth's seawater. This supports the theory that Earth's oceans might have originated from comets. However, the Rosetta probe found that Comet 67P has a ratio three times higher than Earth's water. This high measurement has sparked new research into whether asteroids might also have contributed to Earth's water.

Deuterium plays a complex role in the life cycles of stars. While it is produced by the slow stellar proton-proton chain, it is also rapidly destroyed by fusion.

Deuterium Ionized
Deuterium Ionized

In the hot interiors of stars like the Sun, deuterium is consumed much faster than it is created. This means there is very little deuterium left in the center of stars. However, it persists in the outer solar atmosphere. The existence of deuterium at a constant fraction in all hydrogen is a key piece of evidence for the Big Bang theory. It helps scientists distinguish the Big Bang model from other theories like the Steady State theory.

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🖼️ Images & Media (6)
File:Hydrogen deuterium glow comparison.png
Hydrogen deuterium glow comparison.png
File:Standard Model Deuterium.svg
Standard Model Deuterium.svg
File:Deuterium Ionized.jpg
Deuterium Ionized.jpg
File:Deuterium lamp 1.png
Deuterium lamp 1.png
File:Urey.jpg
Urey.jpg
File:Ivy Mike Sausage device.jpg
Ivy Mike Sausage device.jpg
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