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This chemistry glossary offers definitions for terms which are commonly used in chemistry and chemical engineering. An engineering glossary is available, too. abrasive absolute error absolute pressure absolute temperature absolute uncertainty absolute zero absorbance absorption absorption cross section absorption spectroscopy absorption spectrum absorptivity accelerator accuracy acetate acid acid anhydride acid-base titration acid dissociation constant - Ka acidic solution actinides activated complex activation energy - Ea actual yield addition polymer addition reaction adhesive adsorption aerosol alchemy alcohol aldehyde alkali metal alkaline alkaline earth metal alkane alkene alkyl group alkyne allotrope alloy alpha particle alternating copolymer ammeter amorphous analytical chemistry anion androgen anisotropy annealing antiferromagnetism antioxidant aromatic compound aqueous solution Arrhenius rate equation astrochemistry atactic atom atomic mass atomic mass unit (amu) atomic num...

Soap is good at cleaning because it acts as an emulsifier, enabling one liquid to disperse into another immiscible liquid. While oil (which attracts dirt) doesn't naturally mix with water, soap can suspend oil/dirt in such a way that it can be removed. It's easy to demonstrate the action of an emulsifer. All you need are two immiscible liquids and a little dishwashing detergent or soap. Emulsifier Demo Materials water kerosene or oil dishwashing detergent or soap flask or clear glass Perform the Demonstration Add some kerosene or oil together with some water in a flask. Swirl the contents around to try to mix them. What happens? Add a squirt of dishwashing liquid. Swirl or shake the flask to mix the ingredients. How has the layer of kerosene or oil been changed? What could be easier, right?

As silver oxidizes it will tarnish. This layer of oxidation can be removed without polishing and scrubbing by simply dipping your silver in this non-toxic electrochemical dip. Another big advantage to using a dip is that the liquid can reach places a polishing cloth cannot. You can use chemistry to removethe tarnish from your silver without even touching it. Mel Curtis, Getty Image Difficulty: Easy Time Required: Minutes Here's How: Line the bottom of the sink or a glass baking dish with a sheet of aluminum foil. Fill the foil-lined container with steaming hot water. Add salt (sodium chloride) and baking soda (sodium bicarbonate) to the water. Some recipes call for 2 tsp baking soda and 1 tsp salt, whereas others call for 2 tablespoons each of baking soda and salt. Personally, I wouldn't measure the amounts... just add a bit of each substance. Drop the silver items into the container so that they are touching each other and resting on the foil. You will be able to watch the ta...

Here's a cute cartoon to brighten your day. Sulfur pentafluoride presumably binds with itself to make disulfur decafluoride, a chemical warfare pulmonary agent similar to your good old friend phosgene . Fun stuff. Disulfur decafluoride eventually decomposes into sulfur hexafluoride (which can be used as a sort of anti-helium in gas density demonstrations ) and sulfur tetrafluoride (which reacts with moisture in the air to form sulfurous acid and hydrofluoric acid). Incidentally, while I have no idea about the color of sulfur pentafluoride, I can tell you disulfur decafluoride is colorless and one breath can kill you in a day. It takes a while because its actually the acids produced by the sulfur tetrafluoride reacting with water that likely do you in.

One of my self-improvement projects has been to try to learn how to write legibly. It would be easy to blame my handwriting on being left-handed, but it probably has a lot more to do with trying to write quickly rather than neatly. So, I got a pen and some ink and have been practicing. Ink is one of the practical contributions of chemistry. You can make invisible inks and tattoo inks in addition to writing and drawing inks. Although ink recipes may be closely-guarded secrets, the basic principles of preparing ink are simple. You want to mix a pigment with a carrier (usually water). It helps to include a chemical which will allow the ink to flow fluidly and adhere to the paper (gum arabic). Here are some easy ink recipes to get you started ma Black Permanent Ink 1/2 tsp lamp black (which you can buy or can make by holding a plate over a candle and collecting the soot or from collecting other char) 1 egg yolk 1 tsp gum arabic 1/2 cup honey Mix together the egg yolk, gum arabic, and ho...

Here's an easy and colorful chemistry demonstration for you. Take a long glass tube and fill it with Universal Indicator solution. Add a few drops of 0.02M HCl to one end of the tube and seal it with a stopper. Add a couple of drops of 0.02M NaOH to the other end of the tube and seal it. The Universal Indicator will respond to the pH gradient by providing you with a lovely rainbow. You can invert the tube a few times to speed things up. You can get a similar result using home chemistry. Fill a clear straw with red cabbage juice . Add a little lemon juice or vinegar to one end of the straw. Add a few drops of baking soda or laundry detergent solution to the other end of the straw.

November 13 th is Edward Doisy's birthday. Doisy was an American biochemist who shared the 1943 Nobel Prize in Medicine with Henrik Dam for their work concerning vitamin K. Dam discovered the vitamin and Doisy identified, isolated, determined the structures, and synthesized of two different forms of vitamin K. Vitamin K is actually a group of vitamins named after "Koagulations-Vitamin" in German because they are required for processes of blood coagulation. They are also involved in the process of binding calcium during bone metabolism. Deficiency is rare in adults, but newborns have a higher risk, and an injection of vitamin K1 is recommended by the American Academy of Pediatrics shortly after birth. Other research into the K vitamins is looking at links between vitamin K and bone health, Alzheimer's disease, and certain cancers.