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Acid salt is a term for a class of salts formed by the partial neutralization of diprotic or polyprotic acids. Because the parent acid is only partially neutralized, one or more replaceable hydrogen atoms remain. Typical acid salts have one or more alkali (alkaline) metal ions as well as one or more hydrogen atoms. Well known examples are sodium bicarbonate (NaHCO3), sodium hydrosulfide (NaHS), sodium bisulfate (NaHSO4), monosodium phosphate (NaH2PO4), and disodium phosphate (Na2HPO4). Often acid salts are used as buffers.〔Most introductory chemistry textbooks discuss this area, representative is Zumdahl, S. S. “Chemistry” Heath, 1986: Lexington, MA. ISBN 0-669--04529-2.〕 For example, the acid salt sodium bisulfate is the main species formed upon the ''half'' neutralization of sulfuric acid with sodium hydroxide: :H2SO4 + NaOH → NaHSO4 + H2O Acid salts compounds can act either as an acid or a base: addition of a suitably strong acid will protonate anions, and addition of a suitably strong base will split off H+. The pH of a solution of an acid salt will depend on the relevant equilibrium constants and the amounts of any additional base or acid. A comparison between the ''K''b and ''K''a will indicate this: if ''K''b > ''K''a, the solution will be basic, whereas if ''K''b < ''K''a, the solution will be acidic. In other words you can say that an acid salt is formed when a strong acid reacts with a weak base and vice versa for basic salt. ==Use in food== (詳細はcream of tartar, calcium phosphate, and citrates. High-temperature acid salts produce a leavening effect during baking and are usually aluminium salts such as calcium aluminium phosphate. Some acid salts may also be found in non-dairy coffee creamers. 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「acid salt」の詳細全文を読む スポンサード リンク
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