Computer Sciences
Computer scientists at University of California, Davis, Maynooth University in Ireland and the California Institute of Technology have created DNA molecules that can self-assemble into patterns essentially by running their ...
Mar 20, 2019
0
1728
Engineering
(Tech Xplore)—A team of researchers from the U.S. and China has demonstrated electronic devices that can degrade and disappear on demand using nothing but moisture in the air. In their paper published on the open access ...
Energy & Green Tech
How can we store solar energy for period when the sun doesn't shine? One solution is to convert it into hydrogen through water electrolysis. The idea is to use the electrical current produced by a solar panel to 'split' water ...
Aug 25, 2016
2
3165
Energy & Green Tech
As hydrogen inside fuel cells can generate electrical power, scalable methods to reliably split water into hydrogen and oxygen could have valuable implications for the energy industry. These methods could help to produce ...
Computer Sciences
Molecular computing is a promising area of study aimed at using biological molecules to create programmable devices. This idea was first introduced in the mid-1990s and has since been realized by several computer scientists ...
Energy & Green Tech
Humans can do lots of things that plants can't do. We can walk around, we can talk, we can hear and see and touch. But plants have one major advantage over humans: They can make energy directly from the sun.
Jun 15, 2021
2
1374
Computer Sciences
A pair of researchers at MIT have found evidence suggesting that a new kind of computer could be built based on liquid crystals rather than silicon. In their paper published in the journal Science Advances, Žiga Kos and ...
Energy & Green Tech
The search for renewable energy sources, which include wind, solar, hydroelectric dams, geothermal, and biomass, has preoccupied scientists and policymakers alike, due to their enormous potential in the fight against climate ...
Jun 9, 2020
11
412
Engineering
Northwestern University researchers have raised the standards again for perovskite solar cells with a new development that helped the emerging technology hit new records for efficiency.
Nov 18, 2023
0
80
Energy & Green Tech
Researchers from the University of Twente, in collaboration with Shell, developed a new mechanism that makes the conversion of carbon dioxide into carbon monoxide, which is an essential feedstock in the production of chemicals.
Nov 8, 2022
0
392
A molecule is defined as a sufficiently stable, electrically neutral group of at least two atoms in a definite arrangement held together by very strong (covalent) chemical bonds. Molecules are distinguished from polyatomic ions in this strict sense. In organic chemistry and biochemistry, the term molecule is used less strictly and also is applied to charged organic molecules and biomolecules.
In the kinetic theory of gases the term molecule is often used for any gaseous particle regardless of its composition. According to this definition noble gas atoms are considered molecules despite the fact that they are composed of a single non-bonded atom.
A molecule may consist of atoms of a single chemical element, as with oxygen (O2), or of different elements, as with water (H2O). Atoms and complexes connected by non-covalent bonds such as hydrogen bonds or ionic bonds are generally not considered single molecules.
No typical molecule can be defined for ionic crystals (salts) and covalent crystals (network solids), although these are often composed of repeating unit cells that extend either in a plane (such as in graphene) or three-dimensionally (such as in diamond or sodium chloride). The theme of repeated unit-cellular-structure also holds for most condensed phases with metallic bonding. In glasses (solids that exist in a vitreous disordered state), atoms may also be held together by chemical bonds without any definable molecule, but also without any of the regularity of repeating units that characterises crystals.
This text uses material from Wikipedia, licensed under CC BY-SA
