Related Experiment Video
Updated: Jan 27, 2026
10:01
In Situ High Pressure Hydrogen Tribological Testing of Common Polymer Materials Used in the Hydrogen Delivery Infrastructure
Published on: March 31, 2018
8.0K
Helium-hydrogen immiscibility at high pressures
Yu Wang1, Xiao Zhang1, Shuqing Jiang1
1Key Laboratory of Materials Physics and Center for Energy Matter in Extreme Environments, Institute of Solid State Physics, Chinese Academy of Sciences, Hefei, Anhui 230031, China.
The Journal of Chemical Physics
|March 24, 2019
Summary
Hydrogen and helium mixtures show no miscibility or reactivity under extreme pressures. This research establishes a baseline for understanding these abundant elements in planetary interiors.
Area of Science:
- Planetary Science
- High-Pressure Physics
- Materials Science
Background:
- Hydrogen and helium are the most abundant elements in the universe.
- These elements form the interiors of gas giant planets.
- Understanding their behavior at extreme conditions is crucial for planetary science.
Purpose of the Study:
- Investigate the miscibility, chemical reactivity, and compound formation of hydrogen-helium mixtures at high pressures.
- Establish a baseline for future research on the He-H2 system under extreme conditions.
Main Methods:
- Experiments were conducted using diamond anvil cells.
- Raman spectroscopy, visual observation, and synchrotron X-ray diffraction were employed.
- Compressed gas mixtures of H2-He (1:1) and D2-He (1:10) were studied up to 100 GPa at 300 K.
Main Results:
- No evidence of miscibility between hydrogen and helium was observed.
- No signs of chemical reactivity or new compound formation were detected.
- Results were compared with data on pure bulk materials.
Conclusions:
- The He-H2 system does not exhibit miscibility or reactivity at the studied extreme conditions (up to 100 GPa, 300 K).
- This study provides a critical baseline for future investigations into the behavior of hydrogen and helium mixtures under planetary interior conditions.
Related Concept Videos
00:26Hydrogen Bonds
132.2K
Hydrogen bonds are weak attractions between atoms that have formed other chemical bonds. One of these atoms is electronegative, like oxygen, and has a partial negative charge. The other is a hydrogen atom that has bonded with another electronegative atom and has a partial positive charge.
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
Hydrogen Bonds Control the World!
Because hydrogen has very weak electronegativity when it binds with a strongly electronegative atom, such as oxygen or nitrogen, electrons in the bond are unequally shared....
132.2K
01:04Hydrogen Bonds
13.7K
A hydrogen bond is formed when a weakly positive hydrogen atom already bonded to one electronegative atom (for example, the oxygen in the water molecule) is attracted to another electronegative atom from another polar molecule, such as water (H2O), hydrogen fluoride (HF), or ammonia (NH3). The huge electronegativity difference between the H atom (2.1) and the atom to which it is bonded (4.0 for an F atom, 3.5 for an O atom, or 3.0 for an N atom), combined with the very small size of an H atom...
13.7K
02:34Vapor Pressure
40.2K
When a liquid vaporizes in a closed container, gas molecules cannot escape. As these gas phase molecules move randomly about, they will occasionally collide with the surface of the condensed phase, and in some cases, these collisions will result in the molecules re-entering the condensed phase. The change from the gas phase to the liquid is called condensation. When the rate of condensation becomes equal to the rate of vaporization, neither the amount of the liquid nor the amount of the vapor...
40.2K
03:03Mixtures of Gases: Dalton's Law of Partial Pressures and Mole Fractions
43.8K
Unless individual gases chemically react with each other, the individual gases in a mixture of gases do not affect each other’s pressure. Each gas in a mixture exerts the same pressure that it would exert if it were present alone in the container. The pressure exerted by each individual gas in a mixture is called its partial pressure.
43.8K
02:57Definition and Measurement of Pressure: Atmospheric Pressure, Barometer, and Manometer
42.8K
Gas pressure is caused by force exerted by gas molecules colliding with the surfaces of objects. Although the force of each collision is very small, any surface of an appreciable area experiences a large number of collisions in a short time, which can result in high pressure.
42.8K
02:13Reduction of Alkenes: Catalytic Hydrogenation
14.0K
Alkenes undergo reduction by the addition of molecular hydrogen to give alkanes. Because the process generally occurs in the presence of a transition-metal catalyst, the reaction is called catalytic hydrogenation.
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
Metals like palladium, platinum, and nickel are commonly used in their solid forms — fine powder on an inert surface. As these catalysts remain insoluble in the reaction mixture, they are referred to as heterogeneous catalysts.
The hydrogenation process takes place on the...
14.0K