French Fixie

0

Posted by scot | Posted in Track & Mountain Bikes | Posted on

Tags: bicycle, bike, fixie, velo,

Account limit of 2000 requests per hour exceeded.

French Fixie

French Fixie

The Genesis of Acids and Alkalis

In ancient times, the Egyptians and Greeks defined certain substances based upon their taste. Both the Greeks and the Egyptians had discovered that one particular substance was very sour. This became to be known as vinegar, which was produced from the fermentation of fruits to produce wine. Therefore, a new categorization of substances was developed that included all things that were sour.

The Greeks were also familiar with a different category of substances. They found three slippery substances left behind as residue after burning certain materials. These three substances were: potash, soda, and lime. Potash, which must have been the first to be discovered, was produced from wood ashes. When some waters were produced and allowed to evaporate, the film left behind was soda. Lime was produced from burning seashells. Ultimately, the Greeks discovered a new category to define substances based upon the property of feeling slippery.

In 1386, to build on the Greek’s definition of sour or slippery, a new terminology was developed to speak about things that felt slippery. From the Arabic word al-qaliy, which means “the ashes”, the term alkaline was developed. This word was then used to speak about things that felt slippery.

During the middle ages, the advancement towards defining sour and slippery substances was slow. European trading with China led to the introduction of the highly valued clothing good, silk. During the 16th century in France, fabric dyers found that when particular chemicals were added to the dying agent, the colors became more vibrant and even changed colors. Deeper and richer colors could be produced by adding these chemicals to the dying vats. The dyers noticed that when one chemical was added to the vat, it turned the dye a red color. On the other hand, when a different chemical was added to the vat, it turned the dye to a bluish-green color.

The fabric workers understood that certain substances changed the color and intensity of the dyes used in the industry. At that time they did not need to know how it worked; they just needed to know that the dyes changed colors. For this reason, the fabric workers did not know that the dyes introduced another method for distinguishing between substances the Greeks defined as sour and slippery. Also, there was not a good understanding of the definition of alkaline, except that alkali substances were slippery. Therefore, the phenomenon was overlooked by the fabric workers and science all together.

As trading with China’s silk continued, Europeans were also obtaining precious metals such as gold and silver. However, these metals were often mixed together to produce an alloy. In 1626, an attempt to separate gold from silver led to an important advancement towards understanding substances that were only definable by their taste and texture. It was found that the sour substances defined by the Greeks also could dissolve silver. When a sour substance was added to the gold/silver alloy and allowed to boil, the silver dissolved. After the solid gold pieces were removed, the silver was then re-obtained by allowing the sour substance to boil away. This discovery of the dissolving properties of sour tasting substances led to a new terminology. From the Latin word acidus, which means “sour”, the term acid was developed. This term was then used to define sour tasting substances that had dissolving properties.

Johann Rudolph Glauber began as a pharmacist; however, he soon changed his line of work and became an alchemist. Living in Amsterdam, Glauber ran many experiments concerning acids and alkalis, which were not yet distinctly defined. In his laboratory, he ran many experiments and observed their reactions. A few significant discoveries Glauber made were that of spiritus salis (hydrochloric acid), spirit of alum (sulfuric acid), and spiritus acidus nitri (nitric acid). Spirit of alum and spiritus acidus nitri were used for separating gold and silver; however, he was the first to produce concentrated amounts of either chemical. From his experiments of these three compounds with various chemicals, Glauber noticed that some chemicals reacted violently with one another producing an effervescence effect.

In 1658, he described these violent reactions as being a “battle”:

“When nitri fixi (potassium carbonate, a base) is added to spiritom nitri (nitric acid)…the spiritus acidus and liquior fixus have slain each other”

The fact that acids and alkalis “battle” one another is not the only significant discovery made by Glauber. Also in 1658, Glauber noted that when an acid and an alkali react, they produce a new kind of compound called a salt:

“Liquor fixus (potassium hydroxide alkali) and spiritus acidus nitri (nitric acid) are in their nature…totally unlike, foes and adversaries of each other…and when the two are brought together…and the one part has overcome and killed the other, neither liquor nor a spiritus acidus can be found in their dead bodies, but the same has been made, as both were before and from which they were derived, namely ordinary saltpeter (potassium nitrate salt).”

This observation that an acid and alkali react to yield a salt was a big advancement in acid-alkali alchemy. In fact, this led Glauber to find another important chemical salt. From one of his experiments, Glauber found that when spirit of alum (sulfuric acid) was reacted with ordinary table salt, a new salt was produced. This salt was sal mirabilis (sodium sulfate), which was also called Glauber’s salt. By producing many unattained compounds (hydrochloric acid, nitric acid, sulfuric acid, sodium sulfate, etc.), Glauber’s contributions to alchemy were very important.

With the discoveries presented by Glauber, the chemical world added another terminology that was now broken into three categories: acid, alkali, and salt. What are the properties of these three categories that make them different from one another?

Robert Boyle was born in Ireland where he grew up until he was eight years old. He was then sent to school and traveled around Europe with a French tutor. After his stint of traveling and studying, Boyle returned to Ireland where he joined the Invisible College. The Invisible College was not actually a college at all; it was a group of prominent philosophers who inquired about questions relevant to the time period. This group later became the Royal Society of London for the Improvement of Natural Knowledge after it had been granted by the King of England. Boyle was named to the council and held an important role in the Royal Society.

During the 17th century, the majority view of compounds suggested that all chemical compounds are composed of the same four elements: fire, earth, water, and air. For example, when a log is burned in a fire, it leads to the four elements. The log begins to combust (fire), sap flows from the wood (water), smoke rises from the log (air), and the ashes (earth) are left behind after the log is finished burning. Boyle disagreed with this hypothesis and suggested that differences in compounds were to “different textures” (configuration and cohesion of different elements). For this reason and many others, Boyle was known as the “skeptical chemist”. In fact, Boyle wrote his first book The Skeptical Chemist, which questioned the majority views of alchemy.

Boyle found Glauber’s work interesting. The new category of salts intrigued him and helped to support his hypothesis that not everything is composed of the same four elements. Boyle began experimenting with acids and alkalis. From his experiments, he was able to fit a better definition of an acid and alkali. On top of what the Greeks and Egyptians defined as being sour and what metal purifiers noted as excellent solvents, Boyle added that acids could also precipitate certain substances. Acids were very good in precipitating sulfur. On top of what the Greeks defined as being slippery, Boyle noticed that alkalis also contained “detergent properties”. Alkalis were also good at dissolving sulfur and oils; and just like Glauber, he found that alkalis were good at counteracting the properties of acids. He also noticed that some chemicals do not fit into the category of an acid or alkali.

Boyle continued his research of acids and alkalis and began to conduct experiments concerning how to identify an acid or alkali using indicators. He set up a number of different experiments which he published in his 1664 book Experimental History of Colours. Boyle knew from the French silk dyers that dyes were made from plant juices, so he began to experiment with the affects of acids on certain plant juices. He discovered what the French dyers had known a century before, only now he understood why the phenomenon they observed occurred. He noted that when an acid is placed in a jar containing a purple plant juice, the solution becomes red. Also, when an alkali is reacted with the same purple plant juice, the solution becomes bluish-green. Boyle had rediscovered an interesting and useful means of testing if a chemical was acidic or alkaline.

The development of acid and alkali indicators did not stop there. Boyle began to create small pieces of paper that had been soaked in lichens juice. After the paper had been removed from the juice and dried, it became a soft purple color. When the paper is touched to something acidic in character, the paper becomes red. Likewise, when the paper is touched to something alkaline in character, it becomes bluish-green. This new technique uses the same concept as the plant juice testing, but it is made much simpler by touching paper to the sample.

About the Author

NIKE x BKRW x IAM1 x Bike-Polo Video