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

New clues about how ancient galaxies lit up the universe

NASA's Spitzer Space Telescope has revealed that some of the universe's earliest galaxies were brighter than expected. The excess light is a byproduct of the galaxies releasing incredibly high amounts of ionizing radiation. ...

Graphite coating makes perovskite solar cells waterproof

A cheaper, cleaner and more sustainable way of making hydrogen fuel from water using sunlight is step closer thanks to new research from the University of Bath's Centre for Sustainable Chemical Technologies.

Could this rare supernova resolve a longstanding origin debate?

Detection of a supernova with an unusual chemical signature by a team of astronomers led by Carnegie's Juna Kollmeier—and including Carnegie's Nidia Morrell, Anthony Piro, Mark Phillips, and Josh Simon—may hold the key ...

Seeking disorder as a catalyst for change

Green chemists dream of replicating the reactions of photosynthesis. Of the possible outcomes, one of the most talked about is the ability to make affordable hydrogen fuels from water. In theory, the only by-product of burning ...

Germany's Bosch powers up hydrogen cells for cars

The world's biggest auto parts maker Bosch said Monday it would work with a Swedish firm to develop key components for hydrogen fuel cells designed to power cars, after backing off building electric batteries.

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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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