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The Handy Chemistry Answer Book. Justin P. LomontЧитать онлайн книгу.

The Handy Chemistry Answer Book - Justin P. Lomont


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      The Philosopher’s Stone was an object of legend among alchemists. It was believed that the Philosopher’s Stone possessed the power to make gold from other cheap metals. It has also been said to serve as the elixir of life, which was sought by many alchemists. Of course, such a stone has never been discovered (at least not outside of Hogwarts).

      When did alchemists finally abandon trying to make gold?

      In the late 1700s, a scientist named James Price was still hard at work trying to “transmute” metals into gold and silver. In 1782, he claimed he could convert mercury into silver and gold. At first it appeared that his experiments had worked, but conflict rapidly rose. More and more scientists asked to witness the experiments firsthand, and Price eventually lost confidence in the validity of his own work. After disappearing for a few months, in 1783 he invited scientists to his laboratory to witness his experiments in person, but only a few men showed up. In their presence, Price intentionally ingested a poison, killing himself. He was the last of the modern scientists to claim to have achieved the goals of alchemy, and it is no longer believed that anyone will find a simple way to convert inexpensive metals into gold.

      How did pharmaceutical science get started?

      Paracelsus is credited with being the first person to use chemicals in medicine. Before Paracelsus, people believed that illness and disease were caused by an imbalance in the patient. Hippocrates thought it was an imbalance of the four humours (blood, phlegm, black bile, and yellow bile), and Galen furthered these ideas by assigning a symptom to an imbalance of each of Hippocrates’ humours. These theories supported the use of medical techniques like bloodletting. Paracelsus believed that illness was the result of something from the outside world attacking inside one’s body and that some of the illnesses could be cured by chemicals. He is also known for proposing the basis of toxicology, namely that dosage was critical to whether a substance was poisonous or not.

      What was the first chemistry textbook published?

      Although numerous chemistry texts exist before it, Alchemia, published by Andreas Libavius in 1597, is considered to be the first organized chemistry textbook. Libavius, born in Halle, Germany, in 1555, was a chemist and a medical doctor, and also served as a schoolmaster at the end of his life. In addition to his noteworthy textbook, Libavius is significant in the history of chemistry for further advancing the discipline away from the realm of magic, the occult, and alchemy toward a teachable, logical, and scientific discipline.

      What’s the difference between alchemy and chemistry?

      Let’s ask Robert Boyle, who in 1661 published The Sceptical Chymist, arguing that experiments disproved the idea that the universe was composed solely of Aristotle’s four elements. Boyle himself was an alchemist, in that he believed that one metal could be changed into another, but he was a staunch promoter of the scientific method and helped elevate chemistry to a science. So one could simply say that alchemy is a philosophy, while chemistry is a science.

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      Herbal medications are natural remedies for treating various ailments. Often these are traditional remedies that can date back hundreds of years and are still used today.

      How did early chemistry relate to medicine?

      Early societies all over the world found that certain types of plants could be used for medicinal purposes. Though only relatively recently have people attempted to gain a detailed understanding of the chemistry behind these methods, the overarching reason why these methods work is because a chemical in the plant interacts with the chemicals in your body in a beneficial way.

      What is an herbal medicine?

      Herbal medicines are any plants or plant extracts used for treating ailments, aches, pain, or discomfort. They can range from culinary remedies (like chicken soup for the common cold), to calming extracts (like mint tea), to eating whole herbs. Every ancient civilization seems to have discovered the use of plants as medicines in one form or another. Even as far back as five thousand years ago, humans were using herbal medicines, as evidenced by herbs being found alongside well-preserved, mummified humans like Ötzi the Iceman.

      How were herbal medicines discovered?

      If we had the story of how each and every medicinal herb was discovered, each would likely be an interesting and unique tale. Unfortunately, the use of plants as medicine predates written human history by a few millennia. The earliest written records come from the great ancient civilizations of humankind.

      How are herbal medicines prepared?

      There are many ways of preparing herbal medicines. Tinctures and elixirs are extractions of herbs using some solvent, usually ethanol. If a plant is extracted with acetic acid, the solution is known as a “vinegar,” even though the solvent is also vinegar. A tisane uses hot water to extract herbs—like tea.

      What herbal medicines do people still use today?

      Aspirin and quinine are probably the most famous herbal medicines that have made the transition to mainstream medicine. Many modern medicines were originally isolated from plants, however, but the commercial sources are now usually man-made. For example, Taxol® (paclitaxel) was originally isolated from the Pacific yew tree. In 1967 this compound was found to be useful as a treatment for various types of cancer. For almost thirty years, most of the paclitaxel that was given to patients was obtained from the yew tree. Alternate supplies of this drug were developed in the 1990s, moving this natural drug into the realm of modern synthetic medicines.

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      How do herbal medicines differ from modern medicine?

      Modern pharmaceutical medicines usually contain only one active ingredient, or a few at most. The rest of the ingredients in a pill are there to aid in its delivery in one way or another. Herbal medicines, because they are made from plants that were once living, can contain many more chemicals, though only one may be the active ingredient in this case as well.

      How did chemistry affect trade in ancient times?

      Ancient chemistry was involved in the production of many goods that were important to trade. These included salt, silk, linen dyes, precious metals, wine, and pottery.

      What is fire?

      The chemical description of fire is a combustion reaction. It involves the reaction of oxygen with molecules in some combustible material. The fire itself is caused by energy released by this reaction in the form of heat and light. The fire you see is not only the light that’s being released, but also glowing hot gases.

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      Before matches and butane lighters were invented, people could use flint to start fires for heat and cooking. Striking a hard piece of metal against flint causes a spark, which can in turn catch tinder on fire.

      How can a fire be started with a piece of flint?

      Almost everyone has seen a movie character start a fire using a piece of flint, but you may wonder how this is possible. Flint is a hard stone that can produce sparks when it is struck against a metal, such as steel. The sharp edge of the flint breaks off a small splinter of steel, which is heated significantly by the friction from the strike of the flint. As this splinter of hot steel reacts with oxygen in the air, a spark is produced. The sparks generated in this way can then ignite a piece of dry wood, paper, or other fuel.

      Who first realized that air has weight?

      It was actually a mathematician named


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