Chemical substance

A chemical substance is a form of matter that has constant chemical composition and characteristic properties. It cannot be separated into components by physical separation methods, i.e., without breaking chemical bonds. Chemical substances can be chemical elements, chemical compounds, ions or alloys.

Chemical substances are often called 'pure' to set them apart from mixtures. A common example of a chemical substance is pure water; it has the same properties and the same ratio of hydrogen to oxygen whether it is isolated from a river or made in a laboratory. Other chemical substances commonly encountered in pure form are diamond (carbon), gold, table salt (sodium chloride) and refined sugar (sucrose). However, in practice, no substance is entirely pure, and chemical purity is specified according to the intended use of the chemical.

Chemical substances exist as solids, liquids, gases or plasma, and may change between these phases of matter with changes in temperature or pressure. Chemical reactions convert one chemical substance into another.

Chemistry

Chemistry is a branch of physical science that studies the composition, structure, properties and change of matter. Chemistry includes topics such as the properties of individual atoms, how atoms form chemical bonds to create chemical compounds, the interactions of substances through intermolecular forces that give matter its general properties, and the interactions between substances through chemical reactions to form different substances.

Chemistry is sometimes called the central science because it bridges other natural sciences, including physics, geology and biology. For the differences between chemistry and physics see Comparison of chemistry and physics.

Scholars disagree about the etymology of the word chemistry. The history of chemistry can be traced to alchemy, which had been practiced for several millennia in various parts of the world.

Etymology

The word chemistry comes from the word alchemy which was an earlier set of practices that encompassed elements of chemistry, metallurgy, philosophy, astrology, astronomy, mysticism and medicine. It is often seen as linked to the quest to turn lead or another common starting material into gold. Alchemy, which was practiced around 330, is the study of the composition of waters, movement, growth, embodying, disembodying, drawing the spirits from bodies and bonding the spirits within bodies (Zosimos). An alchemist was called a 'chemist' in popular speech, and later the suffix "-ry" was added to this to describe the art of the chemist as "chemistry".

Drug

A drug is any substance other than food, that when inhaled, injected, smoked, consumed, absorbed via a patch on the skin or dissolved under the tongue causes a physiological change in the body.

In pharmacology, a pharmaceutical drug or medicine, is a chemical substance used to treat, cure, prevent, diagnose a disease or promote well-being. Traditionally drugs were obtained through extraction from medicinal plants, but more recently also by organic synthesis. Pharmaceutical drugs may be used for a limited duration, or on a regular basis for chronic disorders.

Pharmaceutical drugs are often classified into drug classes—groups of related drugs that have similar chemical structures, the same mechanism of action (binding to the same biological target), a related mode of action, and that are used to treat the same disease. The Anatomical Therapeutic Chemical Classification System (ATC), the most widely used drug classification system, assigns drugs a unique ATC code, which is an alphanumeric code that assigns it to specific drug classes within the ATC system. Another major classification system is the Biopharmaceutics Classification System. This classifies drugs according to their solubility and permeability or absorption properties.

Trade

Trade involves the transfer of the ownership of goods or services from one person or entity to another in exchange for other goods or services or for money. Possible synonyms of "trade" include "commerce" and "financial transaction". A network that allows trade is called a market.

The original form of trade, barter, saw the direct exchange of goods and services for other goods and services. Barter is trading things without the use of money. Later one side of the barter started to involve precious metals, which gained symbolic as well as practical importance. Modern traders generally negotiate through a medium of exchange, such as money. As a result, buying can be separated from selling, or earning. The invention of money (and later credit, paper money and non-physical money) greatly simplified and promoted trade. Trade between two traders is called bilateral trade, while trade between more than two traders is called multilateral trade.

Trade exists due to the specialization and division of labor, in which most people concentrate on a small aspect of production, trading for other products. Trade exists between regions because different regions may have a comparative advantage (perceived or real) in the production of some trade-able commodity, or because different regions' size may encourage mass production. As such, trade at market prices between locations can benefit both locations.

Trade (nightclub)

Trade was a highly successful, pioneering and influential gay nightclub started in 1990 by Laurence Malice. Trade was unlike any other club at the time as it opened from 4am until 1pm on Sundays at Turnmills, Clerkenwell Road, London. The club was touted as "the original all night bender". The door policy was firm but fair: "You don't have to be gay or a member to get in, but your attitude and look will count".

Early Years 1990 - 1995

Trade quickly grew in popularity as other clubs at the time such as Heaven, G-A-Y and The Fridge closed at around 02:00-03:00 Sunday mornings, an hour or so before Trade opened at 03.00 Therefore, clubbers were able to go straight on to the club. At the time many guys went cruising in the parks after leaving other clubs. The name 'Trade' and the opening hours was to encourage guys to go to the club as a safer alternative.

Turnmills was the first club in the UK to be given a 24-hour "Music & Dance" licence. This was gained after Laurence Malice had for a long period of time tried to convince Mr Newman that there was a need for people to be able to party in a safe environment after 3am in the morning. Due to this licensing advantage, the venue's role was crucial to the success of Trade.

Trade (gallery)

Trade is an artist run initiative based in Nottingham, UK that has been running since 2008. Trade is curated by the artist Bruce Asbestos and Trade exhibits a range of artworks from performance to sculpture and artists video. The Trade gallery website also has podcast interviews with artists.

Gallery

Trade was listed as one of "the world's best secret art galleries" in 2011 by Alexander Farquharson of Nottingham Contemporary.

Trade shares gallery space at One Thoresby Street, Nottingham.

Exhibitions

Trade has exhibited the artwork of many artists including;

Stuart Sherman, Wasteland Twinning, Jaap Blonk, The Bongoleeros, Vile Plumage, W>A>S>P>S,Paula Roush (with Stewart Home),Phillip Henderson,David Sherry, Robin Deacon, Pyramidd.biz, Mermaid and Monster, Jackie Berridge, Tim Hattrick, Zachary Formwalt, Hannah Conroy, Katy Woods, Eastside Projects, Kelly Large,Beacon, Olivia Plender and Patrick Staff, Bubblebyte, Yelena Popova,Grandad Hill, Ewoud Van Rijn, Iva Kontic,Olaf Breuning, David Blandy and DVVID, M-E-X-I-C-O, Alex Stevenson, Robert Ashley, Reactor, Karin Kihlberg and Reuben Henry, Elisa Pône, Katie Davies,Richard Paul, David SherryMark McGowan (performance artist), Joseph Beuys, Rotterdam VHS Festival, Mark Essen, Ben Woodeson,Oliver Sutherland, Jemma Egan, Tomas Chaffe, Abigail Reynolds, Sarah Doyle, Phillip Henderson, Endless Supply, Artur Zmijewski