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:


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 ...

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 ...

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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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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Have you forgotten your water properties? Check out the video for a review and an explanation as to why ice spikes form.

This reminds me... Gotta go reverse these electrons