2016년 5월 27일 금요일

Acid

Acid

Acid (さん British: acid) is a base and a material working in pairs in chemistry. A general use example of the acid includes acetic acid (I contain around 3-5% to vinegar), (I use it for an electrolyte of the battery of the car) tartaric acid (I use it for baking) sulfate. The acid can be solution, a liquid, a solid so that these three examples show it. Furthermore, like hydrogen chlorides, even a gaseous state can be acid.

Generally, the chemical species which gives proton (H+) or receives an electron pair. Because a definition has been reconsidered while being accompanied by the expansion of the concept, in the chemical history, a definition of the acid which is several kinds exists.

A property to act as acid is called the acidity (さんせい). Generally, the strength of the acid is expressed quantitatively by acidity constant Ka or common logarithm negative pKa.

Because acid and the basic definition are relative concepts, it is not unusual for the material which is acid to work as a base in another system in a certain system. For example, the water acts as Broensted acid giving a proton for the ammonia, but behaves to the hydrogen chloride as a Broensted base receiving a proton.

\rm NH_3 + H_2O\quad \overrightarrow\longleftarrow \quad NH_4^+ + OH^-
\rm HCl + H_2O\quad \overrightarrow\longleftarrow \quad H_3O^+ + Cl^-

I call strong acid, small acid weak acid with the big acid of the acid dissociation constant. Furthermore, I may call the strong acid medium which is acid than 100% sulfuric acid superacid (super strong acid) in particular.

To a compound called "- acid", it presents acidity, and pH of the water solution has many things which are smaller than 7.

Table of contents

Definition of the acid

Only an outline describes below a definition of each acid. The details are articles: See acid and a base.

Arrhenius acid (Arrhenius acid)
The acid by the definition of Arrhenius. The material which gives proton (H+) in a water solution. In a lower expression, the hydrogen chloride (HCl) acts as Arrhenius acid.
HCl → H+ + Cl−
Broensted acid (Brönsted acid)
The acid by the definition of Broensted - Raleigh. The material which gives a proton for reacting partner "B." "AH" or "A+H" is Broensted acid by a bottom-style reaction.
AH + B → A-+ BH+
A+H + B → A + BH+
Lewis acid (Lewis acid)
The acid by the definition of Lewis. The material which receives an electron pair. "A" is a Lewis acid by a bottom-style reaction.
Lewis acid base reaction

Basicity of the acid

Among the hydrogen atoms included in 1 molecule of the acid, the number of hydrogen atoms replaced with a metal atom is called basicity of the acid and calls acid with more than of basicity 2 with polybasic acid.

Monobasic acid

The monobasic acid gives one proton for a child in neutralizing reaction for one minute. (e.g.,: HA = monobasic acid):

HA(aq) + H2O(l) is in equilibrium with H3O+(aq) + A-(aq)         Ka

Polybasic acid

As for the polybasic acid, only the number of basicity can provide a proton at the neutralizing reaction. (e.g.,: H2A= dibasic acid)

H2A(aq) + H2O(l) is in equilibrium with H3O+(aq) + HA-(aq)       Ka1
HA-(aq) + H2O(l) is in equilibrium with H3O+(aq) + A2-(aq)       Ka2

It is generally Ka1 here > It becomes Ka2. The density of polybasic acid fraction is α generally

\alpha_{H_{n-i} A^{i-}} = {{[H^+ ]^{n-i} \displaystyle \prod_{j=0}^{i}K_j} \over {\displaystyle \sum_{i=0}^n \Big[ [H^+ ]^{n-i} \displaystyle \prod_{j=0}^{i}K_j} \Big]}

I can appear.

Representative acid

Allied item

There is an item of the acid in ウィクショナリー.
It is acquired by "https://ja.wikipedia.org/w/index.php?title= acid &oldid=59547849"

This article is taken from the Japanese Wikipedia Acid

This article is distributed by cc-by-sa or GFDL license in accordance with the provisions of Wikipedia.

Wikipedia and Tranpedia does not guarantee the accuracy of this document. See our disclaimer for more information.

In addition, Tranpedia is simply not responsible for any show is only by translating the writings of foreign licenses that are compatible with CC-BY-SA license information.

0 개의 댓글:

댓글 쓰기

피드 구독하기: 댓글 (Atom)