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Question: Who Invented the Periodic Table? Do you know who described the first periodic table of the elements that ordered the elements by increasing atomic weight and according to trends in their properties? I'll give you a hint. It was not Dmitri Mendeleev. The actual inventor of the periodic table is someone rarely mentioned in chemistry history books. Answer: If you answered "Dmitri Mendeleev" then you might be incorrect. Dmitri Mendeleev presented his periodic table of the elements based on increasing atomic weight on March 6, 1869, in a presentation to the Russian Chemical Society. While Mendeleev's table was the first to gain some acceptance in the scientific community, it was not the first table of its kind. John Newlands had published his Law of Octaves in 1865. The Law of Octaves had two elements in one box and did not allow space for undiscovered elements, so it was criticized and did not gain recognition.

Question: What Is Distillation? Answer: Distillation is a widely used method for separating mixtures based on differences in the conditions required to change the phase of components of the mixture. To separate a mixture of liquids, the liquid can be heated to force components, which have different boiling points, into the gas phase. The gas is then condensed back into liquid form and collected. Repeating the process on the collected liquid to improve the purity of the product is called double distillation. Although the term is most commonly applied to liquids, the reverse process can be used to separate gases by liquefying components using changes in temperature and/or pressure. Distillation is used for many commercial processes, such as production of gasoline, distilled water, xylene, alcohol, paraffin, kerosene, and many other liquids. Types of distillation include simple distillation (described here), fractional distillation (different volatile 'fractions' are collec...

Question: Who Was the First Chemist? Chemistry has been around for a very long time! Do you know the name of the first chemist in recorded history? Would it surprise you that the first chemist was a woman? Answer: The first known chemist was a woman. A Mesopotamian cuneiform tablet from the second millenium B.C. describes Tapputi, a perfumer and palace overseer who distilled the essences of flowers and other aromatic materials, filtered them, added water and returned them to the still several times until she got just what she wanted. This is also the first known reference to the process of distillation and the first recorded still.

... not that actually want mosquitoes to bite your friends, but I think you will agree you don't want to be bitten. Here's a list of things that attract mosquitoes. If you want to avoid an encounter with the vampiric swarm you can avoid doing any of these things yourself or you can encourage those around you to do them. Whatever works. Wear Dark Clothing Many mosquitoes use vision to locate hosts from a distance. Dark clothes and foliage are initial attractants. Exercise You give off more carbon dioxide when you are hot or have been exercising. A burning candle or other fire is another source of carbon dioxide. Eat Bananas and French Fries You release more lactic acid when you have been exercising or after eating certain foods (e.g., salty foods, high-potassium foods). Wear Perfume or Cologne In addition to perfumes, hair products, and scented sunscreens, watch for the subtle floral or fruity fragrances from fabric softeners and dryer sheets. Have Col...