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
June 24, 2026
June 24, 2026 A groundbreaking superconducting X-ray spectrometer has begun operation at BESSY II, giving Europe its first TES-based system and boosting photon detection efficiency by up to 1,000 times. The advance enables scientists to explore atomically thin ...
June 23, 2026 A newly proposed quantum sensing technique could make it much easier to identify one of physics’ newest and most intriguing classes of magnets: altermagnets. These unusual materials, discovered only a few years ago, appear to combine the speed and ...
June 23, 2026 NASA’s upgraded Cold Atom Lab is turning the International Space Station into a frontier for quantum research, creating ultra-cold matter that behaves in astonishing ways. The experiments could ...
June 21, 2026 Researchers found that a Chinese sodium-ion battery performs far better than expected, with production quality and design features comparable to Tesla’s batteries. If engineers can improve ...
June 20, 2026 Researchers found that twisting layered sheets of hexagonal boron nitride can dramatically change the light produced by quantum emitters embedded within the material. The technique offers an unexpected new level of control over components that could ...
June 20, 2026 The global cobalt supply chain is more interconnected—and more vulnerable—than previously thought, with disruptions capable of triggering far-reaching cascades across multiple countries and industries. Researchers warn that protecting battery ...
June 17, 2026 A clever nanoscale redesign may have solved one of superconductivity’s biggest problems. Researchers in Sweden discovered that by subtly sculpting the surface beneath an ultrathin superconducting material, they could make it stay superconducting ...
June 16, 2026 Researchers discovered that hydrogen radicals generated by intense UV light can break down stubborn PFAS “forever chemicals” without added chemicals. The breakthrough reveals a key mechanism that could lead to greener and more effective ...
June 15, 2026 Scientists have found that staple-shaped particles can tangle together to create a material that is both strong and flexible. Unlike conventional materials, these particles can be locked into a sturdy structure or rapidly unraveled using vibrations. ...
June 15, 2026 Oxford physicists have created an entirely new type of Schrödinger’s cat-like quantum state using components that are themselves highly quantum in nature. The advance could open new possibilities for more resilient quantum computers and deeper ...
June 14, 2026 A new catalyst design could significantly improve the conversion of CO2 into methanol, an important fuel and chemical feedstock. Researchers separated key reaction steps across different catalyst sites, avoiding a long-standing trade-off between ...
June 12, 2026 A new nature-inspired membrane uses perfectly uniform one-nanometer pores to filter molecules with remarkable precision. The technology could transform industries such as pharmaceuticals and textiles by reducing energy consumption, improving water ...
Latest Headlines
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June 19, 2026 Scientists have uncovered a surprising connection between quantum gravity and an exotic quantum state of matter that could explain why the universe isn’t expanding wildly fast. The study suggests ...
June 18, 2026 A new theory suggests the universe is constantly recording its own history in the fabric of spacetime. If correct, this cosmic memory could help solve some of the biggest puzzles in physics, from ...
June 16, 2026 Physicists have solved a long-standing problem involving systems that appear to violate Newton’s third law, such as bird flocks and bacterial ...
June 14, 2026 What if some black holes aren’t black holes at all? A new theoretical study suggests that when a massive star collapses, it might not form a singularity hidden behind an event horizon. Instead, the ...
June 13, 2026 A bold claim that the universe’s accelerating expansion was an illusion has been put to the test—and failed. Researchers found that the study behind the controversy made key mistakes when ...
June 12, 2026 Deep beneath the ground in China, the massive JUNO neutrino observatory has delivered its first major scientific breakthrough, achieving one of the ...
June 12, 2026 Scientists at RIKEN have proposed a new way to make quantum systems synchronize in only one direction—like a one-way street for sound particles known as phonons. The breakthrough combines two ...
June 11, 2026 Scientists have developed an artificial photosynthesis system that essentially regulates itself, eliminating the need for batteries used in many current designs. The key innovation is an electrolyzer ...
June 11, 2026 Scientists discovered that rice behaves in a highly unusual way: it weakens under rapid compression but stays stronger when pressure is applied ...
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