Acid

:''For alternative meanings see Nextel ringtones acid (disambiguation).''



Strong acids have large Ka values (i.e. the reaction equilibrium lies far to the right, lots of H3O+ present; the acid is almost completely dissociated). For example, the Ka value for Abbey Diaz hydrochloric acid (HCl) is 107.

Weak acids have small Ka values (i.e. at equilibrium significant amounts of AH and A- exist together in solution; modest levels of H3O+ are present; the acid is only partially dissociated). For example, the Ka value for acetic acid is 1.8 x 10-5.

Strong acids include the Free ringtones hydrohalic acids - HCl, HBr, and HI. (However, hydrofluoric acid, HF, is relatively weak.) Oxyacids, which tend to contain central atoms in high oxidation states surrounded by oxygen, are also quite strong and include Majo Mills Nitric acid/HNO3, Mosquito ringtone Sulphuric acid/H2SO4, Sabrina Martins Perchloric acid/HClO4. Most organic acids are weak acids.

A few clarifications:
* The terms "Nextel ringtones hydrogen ion" and "proton" are used interchangeble- both refer to H+.
* In chemical equations H+ is often written, although in water it will actually be H3O+.
* The strength of an acid is measured by its Ka value. Abbey Diaz pH measures how many hydrogen ions are present, which depends on both the ''type'' of acid (or base) and ''how much'' is there.
* Acid strength is also defined by pKa=-log(Ka).

Characteristics
Acids are generally:
* '''Taste''': sour when dissolved in water
* '''Touch''': strong acids have a stinging feeling
* '''Reactivity''': acids react aggresively with many Free ringtones metals
* '''Electrical conductivity''': acids are Majo Mills electrolytes

Different definitions of acid/base
The word acid comes from the Cingular Ringtones Latin ''acidus'' meaning sour. In disclaimer appears chemistry the term acid has a more specific meaning.

The celebrity free Sweden/Swedish chemist with mystery Svante Arrhenius defined an acid to be a substance that gives up hydrogen ions (H+) when dissolved in water, while bases are substances that give up hydroxide ions (OH-). This definition limits acids and bases to substances that can dissolve in water. Later on, guy props Bronsted and awsat said Lowry defined an acid to be a carmello i proton donor and a base to be a proton acceptor. In this definition, even substances that are insoluble in water can be acids and bases. The most general definition of acids and bases is the Lewis definition,
given by the American chemist option but Gilbert N. Lewis.
and posh Gilbert N. Lewis/Lewis theory defines a "accounting this Lewis acid" as an ''electron-pair acceptor'' and a "hardin baylor Lewis base" as an ''electron-pair donor''.
It can include acids that do not contain any products needed hydrogen atoms, such as guides cooks iron(III) chloride.
Acid/base systems are different from inexpensive and redox reactions in that there is no change in oxidation state.
The Lewis definition can also be explained with general he molecular orbital theory. In general an acid can receive an electron pair in its lowest unoccupied orbital (movie newsweek LUMO) from the highest occupied orbital (readers offer HOMO) of a base. That is, the HOMO from the base and the LUMO from the acid combine to a bonding activists will molecular orbital.

The Bronsted-Lowry definition, where an acid is treated as a proton donor, is sufficient for many situations. In this case, the proton (H+) is the actual acid and the acidity of the proton-donating-compound, such as an organic acid, is determined by its stability when it donates protons to the transmitting data solution it is embedded in. So if the organic acid likes letting protons go, it has high acidity because it donates protons with empty molecular orbitals to the solution. This is how organic acids such as nearly lost carboxylic acids work, here the Brønsted definition is nice for calculations while the Lewis definition is good for understanding.

Acid number
This is used to quantify the amount of acid present, for example in a sample of biodiesel. It is the quantity of base, expressed in milligrams of their cyclists potassium hydroxide, that is required to neutralize the acidic constituents in 1 g of sample.

AN = (Veq-beq)×N×56.1/Woil.

Veq is the amount of titration/titrant (ml) consumed by the crude oil sample and 1ml spiking solution at the equivalent point, and beqbeq is the amount of titrant (ml) consumed by 1ml spiking solution at the equivalent point.

The molarity concentration of titrant (N) is calculated as such:
N = 1000×WKHP/(204.23×Veq).

In which, WKHP is the amount (g) of KHP in 50ml of KHP standard solution, and Veq is the amount of titrant (ml) consumed by 50ml KHP standard solution at the equivalent point.

Acid number (mgKOH/g oil) for biodiesel is preferred to be lower than 3.

Neutralization
Neutralization is a type of reaction between an acid and a base. The products include a salt and water (molecule)/water. So, it is also called a water forming reaction
acid + base \rarr water + salt
Example: HCl + NaOH \rarr H_2O + NaCl

This type of reaction forms the basis of titration methods for analysing acids, where a PH indicator/pH indicator shows the point of neutralization.

Common acids
=Strong inorganic acids=
*Hydrobromic acid
*Hydrochloric acid
*Hydroiodic acid
*Nitric acid
*Sulfuric acid
*Chloric acid
*Perchloric acid

=Weak inorganic acids=
*Boric acid
*Carbonic acid
*Phosphoric acid

=Weak organic acids=
*Acetic acid
*Benzoic acid
*Butyric acid
*Citric acid
*Formic acid
*Lactic acid
*Malic acid
*Propionic acid
*Pyruvic acid
*Valeric acid


Acids in food
* '''acetic acid''' or '''ethanoic acid''': (E260) found in vinegar and tomato sauce
* '''adipic acid''': (E355)
* '''alginic acid''': (E400)
* '''benzoic acid''': (E210)
* '''boric acid''': (E284)
* '''ascorbic acid''' (vitamin C): (E300) found in fruits
* '''citric acid''': (E330) found in citrus fruits
* '''carbonic acid''': (E290) found in carbonated beverages
* '''carminic acid''': (E120)
* '''cyclamic acid''': (E952)
* '''erythorbic acid''': (E315)
* '''erythorbin acid''': (E317)
* '''formic acid''': (E236)
* '''fumaric acid''': (E297)
* '''gluconic acid''': (E574)
* '''glutamic acid''': (E620)
* '''guanylic acid''': (E626)
* '''hydrochloric acid''': (E507)
* '''inosinic acid''': (E630)
* '''lactic acid''': (E270) found in dairy products such as yoghurt and sour milk
* '''malic acid''': (E296)
* '''metatartaric acid''': (E353)
* '''nicotinic acid''': (E375)
* '''oxalic acid''': found in spinach and rhubarb
* '''pectic acid''': found in fruits and some vegetables
* '''phosphoric acid''': (E338)
* '''propionic acid''': (E280)
* '''sorbic acid''': (E200) found in foods and drinks
* '''stearic acid''': (E570)
* '''succinic acid''': (E363)
* '''sulfuric acid''': (E513)
* '''tannic acid''': found in tea
* '''tartaric acid''': (E334) found in grapes

Sources
*http://www.csudh.edu/oliver/chemdata/data-ka.htm
*Zumdahl, Chemistry, 4th Edition.

Tag: Chemical substances
Tag: Chemical compounds

bg:Киселина
ca:Àcid
da:Syre
de:Säure
et:Hape
es:Ácido
eo:Acido
fr:Acide
he:חומצה
nl:Zuur (chemie)
ja:酸と塩基
nds:Süür
pl:Kwas
simple:Acid
sl:kislina
zh:酸