acid (redirected from Polyprotic acid)

acid

Any substance that in water solution tastes sour, changes the colour of acid-base indicators (e.g., litmus), reacts with some metals (e.g., iron) to yield hydrogen gas, reacts with bases to form salts, and promotes certain chemical reactions (e.g., acid catalysis). Acids contain one or more hydrogen atoms that, in solution, dissociate as positively charged hydrogen ions. Inorganic, or mineral, acids include sulfuric acid, nitric acid, hydrochloric acid, and phosphoric acid. Organic acids include carboxylic acids, phenols, and sulfonic acids. Broader definitions of acids cover situations in which water is not present. See also acid-base theory.

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(Atomic, Consistent, Isolated, Durable) The properties of a transaction in a well-designed database management system (DBMS). The transaction must be ATOMIC (all updating tasks must be completed or nothing is done), CONSISTENT (it cannot leave the database in a state that violates any integrity rules), ISOLATED (remain invisible to other operations until completed) and DURABLE (will complete or be reversed if the system fails in the interim).

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(programming)

ACID - A mnemonic for the properties a transaction should have to satisfy the Object Management Group Transaction Service specifications. A transaction should be Atomic, its result should be Consistent, Isolated (independent of other transactions) and Durable (its effect should be permanent). The Transaction Service specifications which part of the Object Services, an adjunct to the CORBA specifications.