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Found Acid 14 times.

Displaying results 1 to 10.

1. Acid (adj. acidic) (Arrhenius acid, Lewis acid, Bronsted acid)
A fundamental category of many compounds whose water-based solutions have a sour taste, turn blue litmus paper red, and can combine with metals to form salts. Acids have a pH lower than 7 (strong acids have a pH of less than 3). Specific types of acids include: * Arrhenius acid: any chemical that increases the number of free hydrogen ions (H+) when they're added to a water-based solution. The more free hydrogens produced, the stronger the acid. * Brnsted or Brnsted-Lowry acid: any chemical that acts as a proton donor in a chemical reaction. * Lewis acid: any chemical that accepts two electrons to form a covalent bond during a chemical reaction.

2. Acid dissociation constant (acid ionization constant)
This is the equilibrium constant for the breaking apart of a weak acid into its hydrogen and conjugate base in a water solution.

3. Acid mine drainage
The process to draw off acidic water from a natural mine rich in sulfide minerals which have been oxidized to sulfuric acid by microbial actions.

4. Acid phosphatase
This is an enzyme produced by cells in the prostate (a gland that surrounds the urethra in the base of the penis). It is used to diagnose and follow the progression of prostate cancer. Its level is elevated in prostate cancer, multiple myeloma , bony metastasis of cancers, and is falsely elevated after prostate surgery or examination. (Normal range: range 0.11-0.6 IU/L)

5. Acid proteases
Any of many protein-hydrolyzing enzyme s that work best in an acidic solution (usually in a pH range of 2-6). Such proteases include the stomach enzymes pepsin and rennin . Similar proteases produced by fungi such as Aspergillus oryzae are used in the manufacture of flour and soy sauce.

6. Acid rain
This is rain which has turned acidic because of the presence of sulfur or nitrogen oxides (both created from burning coal and other fossil fuels) in the atmosphere. Acid rain is a serious environmental problem; it can kill trees and harm plants and animals in lakes and ponds.

7. Acid rain
The precipitation of sulfuric acid and other acids as rain. The acids form when sulfur dioxide and nitrogen oxides released during the combustion of fossil fuels combine with water and oxygen in the atmosphere.

8. Acid
A substance that increases the number of hydrogen ions in a solution.

9. Acid-fast stain
A staining technique used to determine the cell wall property of a microorganism. After stained with dye such as hot carbol fuschin, an acid-fast organism, (.e.g. Mycobacterium species) will retain the color in its cell wall after being washed with acid-alcohol.

10. Acidic anhydride
A substance (such as the oxide of a nonmetallic element) that will react with water to form an acid.

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