Related topics: fuel cell · catalyst · hydrogen gas · oxygen · molecules

New study uncovers how hydrogen provided energy at life's origin

Hydrogen gas is a clean fuel. It burns with oxygen in the air to provide energy with no CO2. Hydrogen is a key to sustainable energy for the future. Though humans are just now coming to realize the benefits of hydrogen gas ...

Driving photochemistry with sub-molecular precision

Absorption of light initiates many natural and artificial chemical processes, for example, photosynthesis in plants, human vision, or even 3D printing. Until now, it seemed impossible to control a light-driven chemical reaction ...

Supercharging fuel cells with caffeine

With global goals set on transitioning away from fossil fuels, fuel cells stand out as a promising carbon-free energy source. Comprising an anode and a cathode separated by an electrolyte, fuel cells convert the chemical ...

New catalyst accelerates release of hydrogen from ammonia

Germany can probably only meet its demand for climate-friendly hydrogen by imports, for example, from South America or Australia. For such long-distance transport, hydrogen can be converted into ammonia.

Advancing tissue engineering with shape memory hydrogels

One of the primary goals in the field of tissue engineering and regenerative medicine is the development of artificial scaffolds that can serve as substitutes for damaged tissue. These materials must ideally resemble natural ...

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Hydrogen

Hydrogen (pronounced /ˈhaɪdrədʒən/) is the chemical element with atomic number 1. It is represented by the symbol H. At standard temperature and pressure, hydrogen is a colorless, odorless, nonmetallic, tasteless, highly flammable diatomic gas with the molecular formula H2. With an atomic weight of 1.00794 u, hydrogen is the lightest element.

Hydrogen is the most abundant chemical element, constituting roughly 75% of the universe's elemental mass. Stars in the main sequence are mainly composed of hydrogen in its plasma state. Elemental hydrogen is relatively rare on Earth. Industrial production is from hydrocarbons such as methane with most being used "captively" at the production site. The two largest uses are in fossil fuel processing (e.g., hydrocracking) and ammonia production mostly for the fertilizer market. Hydrogen may be produced from water by electrolysis at substantially greater cost than production from natural gas.

The most common isotope of hydrogen is protium (name rarely used, symbol H) with a single proton and no neutrons. In ionic compounds it can take a negative charge (an anion known as a hydride and written as H−), or as a positively-charged species H+. The latter cation is written as though composed of a bare proton, but in reality, hydrogen cations in ionic compounds always occur as more complex species. Hydrogen forms compounds with most elements and is present in water and most organic compounds. It plays a particularly important role in acid-base chemistry with many reactions exchanging protons between soluble molecules. As the only neutral atom with an analytic solution to the Schrödinger equation, the study of the energetics and bonding of the hydrogen atom played a key role in the development of quantum mechanics.

Hydrogen is important in metallurgy as it can embrittle many metals, complicating the design of pipelines and storage tanks. Hydrogen is highly soluble in many rare earth and transition metals and is soluble in both nanocrystalline and amorphous metals. Hydrogen solubility in metals is influenced by local distortions or impurities in the crystal lattice.

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