Réaksi asam-basa: Béda antarrépisi

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{{Asam-Basa}}
'''Réaksi asam-basa''' hartina [[réaksi kimia]] antara [[asam]] jeung [[basa (kimia)|basa]].
 
==Téori umum asam-basa==
 
=== Definisi Lavoisier ===
Definisi ilmiah munggaran diajukeun ku [[kimiawan]] [[Prancis]], [[Antoine Lavoisier]].
 
Kusabab pangaweruh Lavoisier ngeunaan asam kuat mah utamana ngeunaan asam-oksi, nu condong ngandung atom puseur nu [[wilangan oksidasi|status oksidasina]] luhung dikuriling [[oksigén]], kayaning [[asam nitrat|HNO<sub>3</sub>]] jeung [[asam sulfat|H<sub>2</sub>SO<sub>4</sub>]], jeung kusabab anjeunna mah teu pati awas kana komposisi asam hidrohalat nu sabenerna (HCl, HBr, jeung HI), anjeunna ngahartikeun asam dina jihat kandungan ''oksigén''na, which in fact he named from Greek words meaning "acid-former". When the elements [[chlorine]], [[bromine]], and [[iodine]] were identified and the absence of oxygen in the hydrohalic acids was established by Sir [[Humphry Davy]] in 1810, this definition had to be rejected.
 
=== Definisi Arrhenius ===
 
[[Svante Arrhenius]] nyadiakeun definisi modérn munggaran ngeunaan asam jeung basa dina taun [[1884]]. Dina [[cai]], lumangsung prosés [[konstanta disosiasi|disosiasi]]:
 
:H<sub>2</sub>O &rarr; H<sup>+</sup> + OH<sup>-</sup>
 
Sanyawa nu ngabalukarkeun ngaronjatna kadar H<sup>+</sup> sarta nurunkeun kadar OH<sup>-</sup> disebut '''asam''', mun sabalikna, disebut '''basa'''.
 
'''Asam''' Arrhenius, mun ngalaman disosiasi na cai, bakal ngahasilkeun [[ion]] [[hidrogén]] nu [[muatan listrik|muatanana]] positif jeung ion lawanna nu négatif.
 
'''Basa''' Arrhenius, mun ngalaman disosiasi na cai, bakal ngahasilkeun ion [[hidroksida]] nu muatanana négatif jeung ion lawanna.
 
Ion positif ti hiji basa bisa ngahasilkeun [[uyah (kimia)|uyah]] jeung ion négatif ti hiji asam. Pikeun conto, dua [[mol]] basa [[natrium hidroksida]] (NaOH) bisa ngagabung jeung sa-mol asam sulfat (H<sub>2</sub>SO<sub>4</sub>) ngahasilkeun dua mol cai jeung sa-mol natrium [[sulfat]].
 
:2NaOH + H<sub>2</sub>SO<sub>4</sub> &rarr; 2H<sub>2</sub>O + Na<sub>2</sub>SO<sub>4</sub>
 
=== Definisi proton (Brønsted-Lowry) ===
 
Definisi Brønsted-Lowry, dirumuskeun sacara mandiri ku masing-masing [[Johannes Nicolaus Brønsted]] jeung [[Martin Lowry]] taun [[1923]], revolves around an [[acid]]'s ability to donate [[proton (physics)|protons]] (H<sup>+</sup>) to another compound, called a [[Base (chemistry)|base]], in a chemical reaction.
 
Basa hartina akséptor [[proton]]. Dina réaksi asam-basa Brønsted-Lowry, aya kompetisi antara dua basa marebutkeun hiji proton, sahingga mun '''X''' jeung '''Y''' mangrupa dua spésiés, bakal lumangsung kasatimbangan
 
:HX + Y<sup>-</sup> &harr; HY + X<sup>-</sup>
 
Boh HX jeung HY duanana mangrupakeun asam Brønsted-Lowry; boh X<sup>-</sup> jeung Y<sup>-</sup> duanana mangrupakeun basa Brønsted-Lowry. Mun réaksina leuwih loba lumangsung ka kénca, HY mangrupa asam nu leuwih kuat, sedengkeun X<sup>-</sup> basa nu leuwih kuat; mun réaksina géséh ka katuhu, mangka HX asam leuwih kuat, sedengkeun Y<sup>-</sup> basa leuwih kuat.
 
It may be more intuitive to define the stronger of two acids as the one which reacts more completely with a common base. The following shows that this definition gives the same result. Compare the reactions of the two acids HX and HY with the same base Z<sup>-</sup> (in a mixture containing all these species):
:HX + Z<sup>-</sup> &harr; HZ + X<sup>-</sup>
:HY + Z<sup>-</sup> &harr; HZ + Y<sup>-</sup>
If these reactions have equilibrium constants K<sub>X</sub> and K<sub>Y</sub> respectively, then:
:[X<sup>-</sup>][HZ] / [HX][Z<sup>-</sup>]=K<sub>X</sub>
:[Y<sup>-</sup>][HZ] / [HY][Z<sup>-</sup>]=K<sub>Y</sub>
and hence (dividing):
:[X<sup>-</sup>][HY] / [HX][Y<sup>-</sup>] = K<sub>X</sub> / K<sub>Y</sub>
 
Given that this last quantity is the equilibrium constant for the above reaction, the reaction will tend to the right if K<sub>X</sub>&nbsp;/&nbsp;K<sub>Y</sub>&nbsp;&gt;&nbsp;1, in other words if HX is a stronger acid than HY under this definition, and ''vice versa''.
 
Acids and bases in the Brønsted-Lowry system occur in '''conjugate pairs'''; in the reaction
 
:HX &rarr; H<sup>+</sup> + X<sup>-</sup>
 
'''HX''' is called the [[conjugate acid]] of the base '''X<sup>-</sup>''', and '''X<sup>-</sup>''' is called the [[conjugate base]] of the acid '''HX'''.
 
Some compounds, like [[water]], can act either as an acid or a base, and are called amphoteric compounds.
 
Stronger acids typically oxidize metals, forming salts and releasing hydrogen.
 
See [[pH]] for a measure of proton concentration frequently used for measuring acidity and alkalinity using this definition. For a list of conjugate acid-base pairs, see [[conjugate acid]].
 
=== Definisi pangleyur-sistim ===
 
This definition is based on a generalization of the earlier Arrhenius definition. If we consider a solvent which can be dissociated into a positive species '''X''' and a negative species '''Y''':
 
: XY &harr; X<sup>+</sup> + Y<sup>-</sup>
or
: 2XY &harr; X<sub>2</sub>Y<sup>+</sup> + Y<sup>-</sup>
or
: 2XY &harr; X<sup>+</sup> + XY<sub>2</sub><sup>-</sup>
 
a compound causing an increase in X<sup>+</sup> (or X<sub>2</sub>Y<sup>+</sup>) and a decrease in Y<sup>-</sup> (or XY<sub>2</sub><sup>-</sup>) is an '''acid''' and one causing the reverse is a '''base'''. For example in liquid [[sulfur dioxide]] (SO<sub>2</sub>), [[thionyl]] compounds (formally supplying SO<sup>2+</sup>) behave as acids, and [[sulfites]] (supplying SO<sub>3</sub><sup>2-</sup>) behave as bases.
 
In this more general sense, aprotic compounds (those which do not donate protons), can still react with bases, and the terms "acid" and "base" can still be used for reactions in aprotic or non-aqueous environments.
 
=== Definisi [[éléktron]]ik (Lewis) ===
 
The more general definition offered by [[Gilbert N. Lewis|Lewis]] in [[1923]] (the same year as the Brønsted-Lowry definition) describes the reactivity of an acid in terms of its ability to accept a pair of electrons from a base, defined as an electron-pair donor. In general, an acid reacts with a base by forming a new [[covalent bond]] utilizing an empty [[Electron configuration|orbital]] of the acid to share the extra electron pair of the base. That is an acid-base reaction is the combination of [[HOMO]] from base and [[LUMO]] from acid to form a stable bonding [[molecular orbital]].
 
The Lewis definition is one of the most broad definitions and is necessary for an understanding of acid-base reaction, although the Brønsted-Lowry definition is sufficient and more practical for most cases in everyday use.
 
==Téori asam-basa lianna==
 
=== Definisi Usanovich ===
 
The most general definition is that of the Russian chemist Usanovich, and can basically be summarized as defining an acid as anything that accepts negative species or donates positive ones, and a base as the reverse. This tends to overlap the concept of [[redox]] ([[oxidation]]-[[reduction]]), and so is not highly favored by chemists. This is because redox reactions focus more on physical electron transfer processes, rather than bond making/bond breaking processes, although the distinction between these two processes is somewhat ambiguous.
 
==Sumber rujukan==
*''[http://en.wikipedia.org/wiki/Acid-base_reaction_theories Acid-base reaction theories]'', ti Wikipédia basa Inggris, disalin ping 1 Agustus 2005.
 
==Tempo ogé==
* [[Konsép HSAB]]
* [[Konfigurasi éléktron]]
 
[[Category:Asam-basa]]
 
[[en:Acid-base reaction theories]]
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