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Pearls dissolve in vinegar
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Since pearls are made mostly of calcium carbonate, the acid found in vinegar, known as acetic acid, will definitely dissolve one over a period of time. The same dissolution would occur if an egg were placed in a glass of vinegar and left to sit - the egg shell would disintegrate. Of course, the speed as which the pearl dissolves will depend on the concentration of the acid and the pearl's overall size. The reaction produces calcium acetate, water and carbon dioxide, summarized below: \(\mathrm{CaCO_3+2CH_3COOH\ →\ Ca(CH_3COO)_2+H_2O+CO_2}\) More Pearly Facts: Mollusks actually create pearls as a form of protection from foreign particles, sand and parasites. Natural pearls, though, are very rare in modern times due to a decline in mollusks ...
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5771 |
bio_man |
6 years ago |
New kids on the block
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Back in January, I reported that the periodic table would be getting an update because four new elements were discovered - finally, the new names have been penciled in. Nihonium, moscovium, tennessine, and oganesson will grace the blocks assigned to atomic numbers 113, 115, 117, and 118, said the International Union of Pure and Applied Chemistry (IUPAC) today. Nihonium, discovered by a Japanese team, means “the land of the rising sun,” while moscovium and tennessine are named after places near the labs where they were discovered (Moscow and Tennessee, of course). And oganesson recognizes the work of Russian chemist Yuri Oganessian. By tradition, the right to suggest a name for an element is granted to its discoverer, although IUPAC has ...
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3846 |
duddy |
7 years ago |
Non-Newtonian fluids are no longer a mystery
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A non-Newtonian fluid is a fluid with properties that differ in any way from those of Newtonian fluids - it changes its viscosity almost instantly under stress, so you can punch it as a liquid and it’ll turn into a solid (watch the video below), and you can literally walk across a pool of it. On the contrary, a Newtonian fluid is defined as the perfect fluid, where its viscosity is influenced mostly by its temperature and pressure. So if you have water at a moderate temperature and pressure, it will continue to act like a liquid no matter how much you punch it. Depending on how you manipulate it, the fluid-like substance can change states from a liquid to a solid, but how this happens has remained a conundrum amongst physicists. Scientists ...
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2989 |
duddy |
7 years ago |
First ever image taken of a single protein
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Proteins are subatomic biomolecules. They're produced by cells, so it's logical to assume that they are much tinier than cells, and of course, much tinier than the organelles that produce them. In a remarkable achievement, scientists have now obtained the first-ever photographs of single proteins. Using a "holography electron microscope," researchers tested on a range of protein samples, all just a few nanometers in size. Hemoglobin, the protein that transports oxygen in red blood cells, and cytochrome c, the protein that transfers electrons within the body, were just two examples. Source: arXiv ...
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8422 |
duddy |
8 years ago |
Nature's scuba divers
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Some bugs, such as water scorpions, long-toed water beetle and predaceous diving beetles (shown below) use the molecular properties of water to create miniature scuba diving tanks and spacesuits. The cohesive forces between water molecules essentially makes water molecules "stick" together, allowing bubbles to form against a wall of tension. These little insects are small enough to take advantage of this, by trapping a bubble in their outer wings or tiny bristles on their shell. ...
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8024 |
duddy |
8 years ago |
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18105 |
duddy |
8 years ago |
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9181 |
duddy |
8 years ago |
Definitive proof of water found on Mars
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Since its discovery in 2010, researchers have been trying to solve the mystery of dark streaks that appear and disappear seasonally on the planet's surface (shown above). Scientists are now claiming that this phenomenon, known as the recurring slope lineae, is caused by a bath of saltwater. What is still unknown, however, is where the water is coming from, or if the chemistry is even right for supporting life.
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19306 |
duddy |
8 years ago |
Why do drugs like MDMA make you feel happy?
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This video explains it quite well. The key hormone in question is serotonin. Serotonin is known to play a role in depression. Low serotonin levels are believed to be the reason for depression and associated symptoms of anxiety, apathy, fear, feelings of worthlessness, insomnia and fatigue. The opposite is true when a high-level of serotonin is present, you feel jovial and enthusiastic. MDMA promotes the formation of this hormone. ...
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11008 |
duddy |
8 years ago |
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5894 |
duddy |
8 years ago |
Ice spikes
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Have you forgotten your water properties? Check out the video for a review and an explanation as to why ice spikes form.
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1745 |
ehd123 |
8 years ago |
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2145 |
ehd123 |
8 years ago |
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2646 |
ehd123 |
8 years ago |
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5723 |
duddy |
8 years ago |
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12098 |
duddy |
8 years ago |
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