Acid

An acid (from the Latin acidus/acēre meaning sour) is a chemical substance whose aqueous solutions are characterized by a sour taste, the ability to turn blue litmus red, and the ability to react with bases and certain metals (like calcium) to form salts. An aqueous solution of an acid has a pH of less than 7 and is colloquially also referred to as 'acid' (as in 'dissolved in acid'), while the strict definition refers only to the solute. An acid usually contains a hydrogen atom bonded to a chemical structure that is still energetically favorable after loss of H⁺ (a positive hydrogen ion or proton). A lower pH means a higher acidity, and thus a higher concentration of positive hydrogen ions in the solution. Chemicals or substances having the property of an acid are said to be acidic.

There are three common definitions for acids: the Arrhenius definition, the Brønsted-Lowry definition, and the Lewis definition. The Arrhenius definition defines acids as substances which increase the concentration of hydrogen ions (H⁺), or more accurately, hydronium ions (H₃O⁺), when dissolved in water. The Brønsted-Lowry definition is an expansion to include solvents other than water: an acid is a substance which can act as a proton donor. By this definition, any compound which can be deprotonated can be considered an acid. Examples include alcohols and amines which contain O-H or N-H fragments. A Lewis acid is a substance that can accept a pair of electrons to form a covalent bond. Examples of Lewis acids include all metal cations, and electron-deficient molecules such as boron trifluoride and aluminium trichloride.

Acids in wine

The acids in wine are an important component in both winemaking and the finished product of wine. They are present in both grapes and wine, having direct influences on the color, balance and taste of the wine as well as the growth and vitality of yeast during fermentation and protecting the wine from bacteria. The measure of the amount of acidity in wine is known as the “titratable acidity” or “total acidity”, which refers to the test that yields the total of all acids present, while strength of acidity is measured according to pH, with most wines having a pH between 2.9 and 3.9. Generally, the lower the pH, the higher the acidity in the wine. However, there is no direct connection between total acidity and pH (it is possible to find wines with a high pH for wine and high acidity). In wine tasting, the term “acidity” refers to the fresh, tart and sour attributes of the wine which are evaluated in relation to how well the acidity balances out the sweetness and bitter components of the wine such as tannins. Three primary acids are found in wine grapes: tartaric, malic and citric acids. During the course of winemaking and in the finished wines, acetic, butyric, lactic and succinic acids can play significant roles. Most of the acids involved with wine are fixed acids with the notable exception of acetic acid, mostly found in vinegar, which is volatile and can contribute to the wine fault known as volatile acidity. Sometimes, additional acids, such as ascorbic, sorbic and sulfurous acids, are used in winemaking.

Acid (disambiguation)

An acid is any chemical compound that, when dissolved in water, gives a solution with a pH less than 7.0.

Acid or ACID may also refer to:

Science

Computing

Music

Genres

Bands

Acid (band)

Acid was a Japanese rock band originally created by Hideki after Siam Shade disbanded.

Musical styles

In the beginning, Hideki had a huge influence on Acid and they played a mix of alternative metal and emo with emphasis placed on his and Junpei's twin vocals. After he left the band in 2005, their songs became less focused on vocals and turned a bit more pop-ish, but still kept their "heavy" sound due to having three guitarists.

History

Acid formed in August 2003 through auditions held by Hideki. Their live setlist was made up of both of Hideki's solo albums at the beginning and, after one year of excessive touring through Japan, the group went into the studio at the end of 2004 to record their first album. Acid 1.5: Punk Drunker was released in March 2005.

With the end of Siam Shade, Hideki didn't want people to always compare his new band with the old one when he was singing. That's why he drew back to the position behind the keyboard at first and later on left Acid completely in June 2005 so that the band were able to go their own way. Furthermore, he says that this group is his pride and that he'd like to see them in Tokyo Dome one day.

Lysergic acid diethylamide

Lysergic acid diethylamide (/daɪ eθəl ˈæmaɪd/ or /æmɪd/ or /eɪmaɪd/), abbreviated LSD or LSD-25, also known as lysergide (INN) and colloquially as acid, is a psychedelic drug of the ergoline family, well known for its psychological effects—which can include altered thinking processes, closed- and open-eye visuals, synesthesia, an altered sense of time, and spiritual experiences—as well as for its key role in 1960s counterculture. It is used mainly as an entheogen and recreational drug. LSD is not addictive. However, acute adverse psychiatric reactions such as anxiety, paranoia, and delusions are possible.

LSD was first synthesized by Albert Hofmann in 1938 from ergotamine, a chemical derived by Arthur Stoll from ergot, a grain fungus that typically grows on rye. The short form "LSD" comes from its early code name LSD-25, which is an abbreviation for the German "Lysergsäure-diethylamid" followed by a sequential number. LSD is sensitive to oxygen, ultraviolet light, and chlorine, especially in solution, though its potency may last for years if it is stored away from light and moisture at low temperature. In pure form it is a colorless, odorless, tasteless solid. LSD is typically either swallowed (oral) or held under the tongue (sublingual), usually on a substrate such as absorbent blotter paper, a sugar cube, or gelatin. In its liquid form, it can also be administered by intramuscular or intravenous injection. Interestingly, unlike most other classes of illicit drugs and other groups of psychedelic drugs such as tryptamines and phenethylamines, when LSD is administered via intravenous injection the onset is not immediate, instead taking approximately 30 minutes before the effects are realized. LSD is very potent, with 20–30 µg (micrograms) being the threshold dose.

Acid house

Acid house is a subgenre of house music developed around the mid-1980s by DJs from Chicago. The defining feature of a "squelching" bass sound was produced using the Roland TB-303 electronic synthesizer-sequencer. Acid house spread to the United Kingdom and continental Europe, where it was played by DJs in the acid house and later rave scenes. By the late 1980s, acid house had moved into the British mainstream, where it had some influence on pop and dance styles.

Acid house brought house music to a worldwide audience. The influence of acid house can be heard on later styles of dance music including trance, Goa trance, psychedelic trance, breakbeat, big beat, techno and trip hop.

Characteristics

Acid house's minimalist production aesthetic combined house music's ubiquitous programmed 4/4 beat with the electronic ‘squelch' sound produced by the Roland TB-303 electronic synthesizer-sequencer by constantly modulating its frequency and resonance controls to create 'movement' in otherwise simple bass patterns. Other elements, such as synthetic strings and stabs, were usually minimal. Sometimes tracks were instrumentals such as Phuture's "Acid Tracks", or contained full vocal performances such as Pierre's Pfantasy Club's "Dream Girl", while others were essentially instrumentals complemented by the odd spoken word 'drop-in', such as Phuture's "Slam".