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Showing posts from February 21, 2010

Natural Easter Egg Dyes

It's fun and easy to use foods and flowers to make your own natural Easter egg dyes. The two main ways to use your own dyes are to add dyes to the eggs when boiling them or to dye the eggs after they have been hard-boiled. It's a lot faster to boil the dyes and eggs together, but you will use several pans if you want to make multiple colors. Dyeing the eggs after they have been cooked takes as many dishes and more time, but may be more practical (after all, most stoves only have four burners!). Try both fresh and frozen produce. Canned produce will produce much paler colors. Boiling the colors with vinegar will result in deeper colors. Some materials need to be boiled to impart their color (name followed by 'boiled' in the table). Some of the fruits, vegetables, and spices can be used cold. To use a cold material, cover the boiled eggs with water, add dyeing materials, a teaspoon or less of vinegar, and let the eggs remain in the refrigerator until the desired color

Easter Chemistry Projects

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If you celebrate Easter, there are several projects you can do that will add a bit of educational chemistry-related fun to the holiday season. If you want to get an early start, it's fun to dye hollowed eggs before Easter or make a sugar crystal string Easter egg for an Easter decoration.

Rohypnol or Roofies Drug Facts

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Would you recognize the drug Rohypnol (roofies) if you saw it? Rohypnol is sometimes called the "date rape drug" because a person who takes the drug may be incapacitated and also unable to recall events which occurred under the influence of the drug. While Rohypnol used to be manufactured as a white pill, which could be crushed and dissolved in a liquid such that it was invisible, the drug is now supplied as a green tablet that contains a blue dye. The dye is intended to be visible if an attempt is made to dissolve the drug in a drink, though obviously the color wouldn't be noticeable in a blue or dark-colored beverage. I've added some quick facts about Rohypnol to my drug facts index so you can learn more about this drug and also see what it looks like.

Emerald Crystal Geode

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You can grow this emerald crystal geode by substituting ammonium phosphate for alum (and green food coloring) in this easy geode project.

Easy Violet Flames

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Violet flames are very easy to make. All you do is sprinkle salt substitute on your fire. Salt substitute contains potassium chloride and potassium bitartrate. If you are familiar with the emission spectra from flame tests, you'll recognize that potassium salts burn violet or purple. To me, the color seems more of a blue-violet, but you can get a more reddish purple if you mix a little strontium from the red fire tutorial in with the salt substitute. Keep in mind, violet is not one of the colors your eyes see really well. The subtle glow of these flames can be completely overwhelmed by the colors from trace impurities. This means two things: (1) Use as pure a fuel as you can. I used Heet™ fuel treatment, which is methanol. If you sprinkle the salt substitute on your wood-burning campfire, the flames will change color but the color won't necessarily be violet. (2) Use salt substitute and not lite salt. Lite salt is a mixture of normal table salt (sodium chloride) with pota

This Day in Science History - February 24 - Inflammable Air

February 24th marks the passing of Henry Cavendish. Cavendish was a British natural philosopher that made meticulous studies of gases. He made extensive studies of the 'airs' he collected including the discovery of hydrogen. He collected hydrogen by collecting the gas given off by the reaction of metals and strong acids and called it 'inflammable air'. Inflammable air was almost entirely made up of phlogiston, the substance in a body that causes them to burn. He found if he combined three parts inflammable air with seven parts of common air and dropped fire into the mixture, it would make a very loud noise and produce water. He also noted that all of the inflammable air and nearly a fifth of the common air was used up in this experiment. Further investigation found if he mixed two parts of inflammable air with one part dephlogisticated air (oxygen) would produce water. We know this reaction today as: 2 H2 (g) + O2 (g) → H2O (l)

What Is the Wavelength of Magenta?

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Here is a picture of the visible spectrum. Can you find the color magenta? Why can't you find magenta in the visible spectrum? This is because magenta cannot be emitted as a wavelength of light. Yet magenta exists; you can see it on this color wheel. Magenta is the complementary color to green, or the color of the afterimage you would see after you stare at a green light. All of the colors of light have complementary colors that exist in the visible spectrum, except for green's complement, magenta. Most of the time your brain averages the wavelengths of light you see in order to come up with a color. For example, if you mix red light and green light, you'll see yellow light. However, if you mix violet light and red light, you see magenta rather than the average wavelength, which would be green. Your brain has come up with a way to bring the ends of the visible spectrum together in a way that makes sense. Pretty cool, don't you think?

Calcium Facts

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Calcium isn't found free in nature, but it can be purified into a soft silvery-white metal. Calcium is the 5th most abundant element in the Earth's crust, present at a level of about 3% in the oceans and soil. The element is essential for animal and plant nutrition. Calcium participates in many biochemical reactions, including building skeletal systems and moderating muscle action. Calcium is a metal. It readily oxidizes in air. Because it makes up such a large part of the skeleton, about one-third of the mass of human body  comes from calcium, after water has been removed. Calcium Atomic Number: 20 Symbol: Ca Atomic Weight: 40.078 Discovery: Sir Humphrey Davy Davy 1808 (England) Electron Configuration: [Ar] 4s 2 Word Origin: Latin calx , calcis : lime Properties: The melting point of calcium is 839 +/- 2°C, boiling point is 1484°C, specific gravity is 1.55 (20°C), with a valence of 2. Calcium is a silvery white, soft alkaline earth metal. Although

What Is Canola Oil?

Did you think there was a canola plant? I never gave it much thought. I mentioned in my biodiesel tutorial that oils which contain tocopherol (Vitamin E) have a longer shelf life than oils that do not contain this natural preservative. I noted that rapeseed oil contains tocopherol... what I didn't say was that canola oil is made from rapeseed. So why don't we just call it rapeseed oil? Blame Canada! I'm joking, but seriously, the word 'canola' was coined in 1978 from 'Canadian oil, low acid'. Canola oil comes from select rapeseed cultivars that produce low erucic acid rapeseed oil and low glucosinolate meal. These cultivars were developed in Canada in the 1970s by Keith Downey and Baldur Stefansson.

This Day in Science History - February 21 - Carl Dam and Vitamin K

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February 21 st is Carl Henrik Dam's birthday. Dam was a Danish biochemist who discovered vitamin K. He was feeding chickens a cholesterol-free diet to find out if they needed cholesterol or not. He discovered the chickens could synthesize some of cholesterol, but several fell ill due to severe internal hemorrhaging. Further testing showed he could prevent this if he added green leaves or liver to their diet. Something in these foods helped the chicken's blood to coagulate, but did not match up with any of the other known vitamins. He called his new coagulation nutrient vitamin K from the German Koagulations-Vitamin. Dam would earn half the 1943 Nobel Prize in Medicine for this discovery. Find out what else occurred on this day in science history .

How To Grow Ammonium Phosphate Crystals

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Monoammonium phosphate is one of the chemicals included in commercial crystal growing kits because it is safe and practically foolproof for producing a mass of crystals quickly. The pure chemical yields clear crystals, but you can add food coloring to get any color you desire. Difficulty: Easy Time Required: one day Here's How: Stir six tablespoons of monoammonium phosphate into 1/2 cup of very hot water in a clear container. I use water heated from an electric drip coffee maker and a drinking glass (which I wash before using it again for beverages). Add food coloring, if desired. Stir until the powder is completely dissolved. Set the container in a location where it won't be disturbed. Within a day, you'll have a bed of long, thin crystals blanketing the bottom of the glass or else a few large single crystals. Which type of crystals you get depend on the rate at which the solution cools. For large single crystals, try to cool the solution slowly from very hot down to

Everyday is special - 21 February 2010

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Also called Ekushey Day, Martyrs’ Day or Language Movement Day, this day commemorates the students who were killed by Pakistani police on Feb. 21, 1952 while they were campaigning for the recognition of Bangla as one of the state languages of Pakistan. After this event, the movement gained momentum and Bangla was recognized as one of the state languages of Pakistan at a session of parliament on May 9, 1954. After the establishment of the People’s Republic of Bangladesh in 1971, this day became a national holiday. At one minute past midnight on Feb. 21, the president of Bangladesh arrives at the Shaheed Minar, the

International Mother Language Day (21 February )

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International Mother Language Day was proclaimed by UNESCO's General Conference in November 1999. The International Day has been observed every year since February 2000 to promote linguistic and cultural diversity and multilingualism. Languages are the most powerful instruments of preserving and developing our tangible and intangible heritage.

Virtual Bangladesh : History : Ekushe February

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2nd Wave January 26, 1952 The Basic Principles Committee of the Constituent Assembly of Pakistan announces its recommendation that Urdu should be the only state language. In a public meting at Paltan Maidan, Dhaka, Prime Minister Nazimuddin declares that Urdu alone will be the state language of Pakistan. Both the developments spark off the second wave of language agitation in East Bengal. January 28, 1952 The students of Dhaka University in a protest meeting call the Prime Minister and the Provincial Ministers as stooges of West Pakistan. January 30, 1952 In a secret meeting called by the Awami League, which is attended by a number of communist front as well as other organizations, it is agreed that the language agitation can not be successfully carried by the students alone. To mobilize full political and student support, it is decided that the leadership of the movement should be assumed by the Awami League under Bhashani.

Virtual Bangladesh : History : Ekushe February

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1st Wave September 15, 1947 Tamuddun Majlis (Cultural Society, an organization by scholars, writers and journalists oriented towards Islamic ideology) in a booklet titled State Language of Pakistan : Bengali or Urdu? demands Bengali as one of the state language of Pakistan. The Secretary of the Majlis, at that time a Professor of Physics in Dhaka University, [Abul Kashem] was the first person to convene a literary meeting to discuss the State Language issue in the Fazlul Huq Muslim Hall, a student residence of Dhaka University. Supporters and sympathizers soon afterwards formed a political party, the Khilafate-Rabbani Party with Abul Hasim as the Chairman. (-- Talukder Maniruzzaman) November 1947 In Karachi, the representatives of East Bengal attending the Pakistan Educational Conference, called by the Minister of Education Fazlur Rahman, a Bengali, oppose Urdu as the only national language. February 23, 1948 Direndra Nath Dutta, a Bengali opposition member, moves a resol