Just under 200 years later a Londoner named Henry Bollmann Condy was a chemist. He had an interest in disinfectants and made some things like "ozonised water". He found that when he melted pyrolusite with sodium hydroxide and dissolved it in water, it made a solution that had good disinfectant properties. He patented this solution, and sold it as "Condy's Fluid". The problem was that the solution was not very stable. This was fixed by using potassium hydroxide rather than sodium hydroxide. This gave a more stable material. It also was able to be dried to the just as good potassium permanganate powder. This powder was called "Condy’s crystals" or "Condy’s powder". Potassium permanganate was easy to make so Condy tried to stop other people from making it and selling it themselves.
Early photographers used it in flash powder.
Potassium permanganate is used as an oxidizing agent. It also is used in disinfectants and in deodorizers. It can be used to make many different kinds of chemicals. In waste water treatment, it is used to get rid of hydrogen sulfide, a stinky toxic gas. In analytical chemistry, an accurate concentration of KMnO is sometimes used to see how much of a certain reducing agent is in the titration. In a related way, it is used as a reagent for wood pulp. Mixing potassium permanganate and formaldehyde makes a mild tear gas.
Dilute solutions of KMnO convert alkenes into diols (glycols). This behaviour is also used as a qualitative test for the presence of double or triple bonds in a molecule, since the reaction makes the permanganate solution colorless. It is sometimes referred to as Baeyer's reagent.
Concentrated solutions oxidize a methyl group on an aromatic ring, e.g. toluene to benzoic acid.
KMnO oxidizes pseudoephedrine hydrochloride to produce methcathinone, a Schedule I drug in the United States. Consequently, the DEA has restricted its use and sale by classifying it as a List I controlled precursor. Potassium permanganate is listed as a Table I precursor under the United Nations Convention Against Illicit Traffic in Narcotic Drugs and Psychotropic Substances.
Concentrated sulfuric acid reacts with potassium permanganate to give manganese(VII) oxide, which can be explosive. . This reaction also makes ozone. The ozone can ignite paper soaked in alcohol. This reaction is very dangerous.
Concentrated HCl makes chlorine.
The Mn-containing products from redox reactions depend on the pH. Acidic solutions of permanganate are reduced to the faintly pink Mn ion, as in manganese(II) chloride. In neutral solution, permanganate is reduced to brown manganese(IV) oxide, where Mn is in a +4 oxidation state. Manganese(IV) oxide is the stuff that stains skin when potassium permanganate is put on it. Potassium permanganate spontaneously reduces in an basic solution to green-coloured potassium manganate, where manganese is in the +6 oxidation state.
Solid potassium permanganate is a strong oxidizer and in general it should be kept separated from reducing agents. Some reactions need a bit of water. For example, powdered potassium permanganate and powdered sugar will ignite (but not explode) a few seconds after a drop of water is added. Dilute solutions of KMnO are not dangerous. KMnO forms dangerous products when mixed with concentrated acids.
Potassium permanganate stains skin and clothing and should be handled with care. Clothing stains may be washed away using acetic acid. Skin stains disappear within 48 hours.
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Silkworm
The silkworm is the larva( the active immature form of an insect)or caterpillar of the Bombyx mori moth. Silk has been made for at least 5000 years in China. The moth is important because it makes silk. It is entirely dependent on humans, and it no longer lives in the wild. Silkworms eat mulberry leaves, and are native to northern China.
The domesticated "B. mori" and the wild "Bombyx mandarina" can still breed and sometimes produce hybrids.
The female silkworm lays about 300 eggs at a time. She lays eggs on the leaves of mulberry trees. The eggs are covered with gelatinous secretion by which they stick to the leaves. The female moth (silkworm) lays eggs and dies after laying eggs as she does not eat anything. The eggs are kept in a cool place so that they can be stored for a long time. In a favorable condition, they hatch into larvae. Larvae are produced in about 2 weeks from eggs at a temperature of 18 to 25 degree Celsius.
The cocoon is made of one thread of raw silk from 300 to 900 meters (1000 to 3000 feet) long. The fibers are very thin. About 2,000 to 5,000 cocoons are needed to make a pound of silk.
If the animal is allowed to survive after spinning its cocoon, it will make a hole in the cocoon when it exits as a moth. This would cut the threads and ruin the silk. Instead, silkworm cocoons are thrown into boiling water, which kills the silkworms and also makes the cocoons easier to unravel. Often, the silkworm itself is eaten.
The adult silkworms (moths) cannot fly. The silkworm-moths have wings about 2 inches wide and a white hairy body. Females and males are similarly colored. Adult silkworms have small mouths and do not eat.
In China, there is a legend that the discovery of the silkworm's silk was first invented by the wife of the Yellow Emperor, Leizu around the year 2696 BC. According to the book written in the 13th century, she was drinking tea under a tree when a cocoon fell into her tea. She picked it out and as it started to wrap around her finger, she slowly felt something warm. When the milk ran out, she saw a small cocoon. In an instant, she realized that this cocoon was the source of the silk. She taught this to the people and it became common. There are many more legends about the silkworm.
Khotan is an oasis, located on the southern edge of Taklamakan Desert, and was one of the first places outside of inland China to begin cultivating silk. In the far past, the Chinese guarded their knowledge of silk. It is said that a Chinese princess smuggled eggs to Khotan, hidden in her hair. After this, the way to cultivate silk was transmitted to the Western Asia, and also Europe.
The Japanese also love silk and started cultivating and weaving silk in the earlier age than the western countries. According to the "Records of the Three Kingdoms", a history book published in the 3rd century, Japan exported silk to "Wei", a kingdom in the northern part of the China mainland, in the 2nd century. It takes 5000 silkworms to make a single kimono.
In Korea, silkworm pupae are boiled and seasoned, then eaten as a popular snack food known as "beondegi".
In China, street vendors sell roasted silkworm pupae. The pupae are a delicacy in the Northern Area of China. They are baked with Satay sauces and rice to add extra flavor.
In Japan, silkworm pupae are usually used as bait to catch fish, and sometimes served as "tsukudani". It can be made by dipping and boiling Silkworm Pupae in a sweet-sour sauce with soy sauce and sugar.
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Death Valley
Death Valley is a National Park in the U.S. state of California. It is the hottest, driest, and lowest place in North America. It is a desert southeast of the Sierra Nevada mountain range. Death Valley is a part of the Mojave Desert. It is the most important part of Death Valley National Park. It is an endorheic basin, which means that the rivers in it do not flow to the sea.