Reference Terms
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Chemical compound
A chemical compound is a chemical substance consisting of two or more different chemically bonded chemical elements, with a fixed ratio determining the composition. The ratio of each element is usually expressed by chemical formula. For example, water (H2O) is a compound consisting of two hydrogen atoms bonded to an oxygen atom.
The atoms within a compound can be held together by a variety of interactions, ranging from covalent bonds to electrostatic forces in ionic bonds. A continuum of bond polarities exist between the purely covalent bond (as in H2) and ionic bonds. For example H2O is held together by polar covalent bonds. Sodium chloride is an example of an ionic compound.
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Matter & Energy News
August 24, 2026
Aug. 23, 2026 Scientists have developed an ultrathin coating that could dramatically improve how efficiently heat is transferred during condensation. By turning tiny polymer structures once considered “defects” into places where water droplets can form, then ...
Aug. 22, 2026 Freezing the liquid core of an optical fiber produced an extreme environment where light and sound interact more than 1,000 times more strongly than in ordinary fibers. Researchers used the effect to create optoacoustic memory, potentially paving ...
Aug. 21, 2026 Scientists watched a light-triggered hidden state form inside a material in only 30 femtoseconds, revealing a step that had never been seen before. The material first entered a fleeting electronic state in which its bonds reorganized in a repeating ...
Aug. 17, 2026 Caltech scientists have created ultra-low-loss optical pathways on silicon chips that approach the efficiency of fiber optics and dramatically outperform existing technology at visible wavelengths. The breakthrough could unlock more powerful lasers, ...
Aug. 16, 2026 Scientists have discovered that tiny, sharply curved wrinkles in graphene can dramatically alter its electrical behavior, creating surprisingly strong charge separation. The finding suggests future electronics could be tuned by reshaping materials ...
Aug. 14, 2026 A tiny superconducting engine has successfully converted heat near absolute zero into useful work, demonstrating the first cyclic quantum heat engine of its kind. Future versions could operate ...
Aug. 12, 2026 Ordinary WiFi networks could quietly become powerful surveillance tools, allowing people to be identified without cameras, special sensors, or even carrying a connected device. Researchers showed that unencrypted signals routinely exchanged between ...
Aug. 11, 2026 Scientists have created an unusually corrosion-resistant stainless steel that could replace costly titanium components used to produce green hydrogen. The breakthrough could reduce structural material costs by roughly 40 times and make ...
Aug. 8, 2026 A new nanostructured carbon design lets fuel-cell catalysts use tiny amounts of platinum while remaining remarkably stable and efficient. The breakthrough could help hydrogen fuel cells become a more practical way to power data centers, vehicles, ...
Aug. 8, 2026 Scientists have created the first quantum material that can sort and transport different quantum states of light at room temperature, potentially removing the need for bulky, ultra-cold refrigeration ...
Aug. 7, 2026 Scientists have generated quantum entanglement directly from sunlight, potentially offering a lower-energy alternative to the lasers normally used in quantum technology. Their outdoor experiment produced entangled photons with about 94% similarity ...
Aug. 7, 2026 Scientists have demonstrated that heat can move through a crystal in focused, wave-like rays at room temperature instead of spreading randomly. The breakthrough could make it possible to route heat around sensitive parts of next-generation chips and ...
Latest Headlines
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Aug. 24, 2026 Researchers have found a way to create a complete 3D image of a molecule’s wavefunction, one of quantum mechanics’ most fundamental yet elusive features. By combining advanced photoelectron ...
Aug. 23, 2026 Researchers at CERN have created microscopic versions of the early Universe by colliding surprisingly small atomic nuclei at nearly the speed of ...
Aug. 21, 2026 Two very different types of quantum particles may be able to form stable droplets that hold themselves together, challenging decades of conventional thinking. The prediction could soon be tested ...
Aug. 21, 2026 For decades, scientists have puzzled over why certain atomic nuclei unexpectedly produce large numbers of low-energy gamma rays. A new experiment traced the effect to magnetic changes inside the ...
Aug. 20, 2026 Extreme experiments have revealed how diamond behaves at crushing pressures beyond those inside Neptune and Uranus, resolving a decades-old conflict ...
Aug. 19, 2026 MIT physicists found that two electronic phases inside the same quantum material emerge through surprisingly different mechanisms—one smoothly and ...
Aug. 19, 2026 A tiny machine made from just an atom and particles of light may sound impossibly simple, but it raises a surprisingly difficult question: what counts as heat, and what energy can still do useful ...
Aug. 18, 2026 A magnetar’s colossal magnetic field may have revealed a quantum effect predicted by Werner Heisenberg nearly 90 years ago, in which seemingly ...
Aug. 18, 2026 Einstein’s abandoned cosmological constant made a spectacular comeback when astronomers discovered that the universe’s expansion is accelerating. ...
Aug. 16, 2026 Physicists may have uncovered a hidden feature inside protons that helps preserve one of matter’s most fundamental properties. RHIC collision data ...