अम्ल

अम्ल (मराठी: ऍसिड) (यक्व थासय् जेनेरिक सूत्र कथं HA [H⁺A⁻]) सांस्कृतिक कथं रसायनिक कम्पाउण्ड ख। थ्व कम्पाउण्डयात लःया सम्पर्कय् तयेबिले छगू सोलुसन पिकई गुकिया हायड्रोजन आयन ऍक्टिव्हिटी शुद्ध लया स्वया अप्व जुइ, वा pH ७.० स्वया म्हो जुइ। थ्व परिभाषा अम्लया आधुनिक परिभाषाया नापं ला। आधुनिक परिभाषाय् जोहानेस निकोलस ब्रोन्स्टेड व मार्टिन लौरीया परिभाषा दु, इमिसं स्वतन्त्र कथं अम्लयात क्षारयात हायड्रोजन आयन (H⁺) बीइगु कम्पाउन्ड धका परिभाषित याना तःगु दु । साधारण दसुलि ऍसेटिक ऍसिड (व्हिनेगरय्) व सल्फ्युरिक अम्ल (कार बॅटरीइ छ्य्‌लिगु) आदि ला। अम्ल/क्षार व्यवस्था रिडक्स रिऍक्शन स्वया पा। अम्ल/क्षार व्यवस्थाय् रिडक्सय् थें ऑक्सिडेशन स्टेट पाइमखु।

परिभाषा

मू पौ: अम्ल-क्षार रियाक्सन दर्शन

"अम्ल" धाःगु खँग्वः संस्कृत शब्दं वःगु ख। रसायन शास्त्रय् दुथने धुंका थ्व खँग्वःयात निश्चित रसायनिक अर्थय् छ्येलिगु या। अम्लयात परिभाषित यायेगु प्यंगु साधारण प्रकृया दु:

आर्हेनियस: According to this definition developed by the Swedish chemist Svante Arrhenius, an acid is a substance that increases the concentration of hydrogen ions (H⁺), which are carried as hydronium ions (H₃O⁺) when dissolved in water, while bases are substances that increase the concentration of hydroxide ions (OH^-). This definition limits acids and bases to substances that can dissolve in water. Around 1800, many French chemists, including Antoine Lavoisier, incorrectly believed that all acids contained oxygen. Indeed the modern German word for oxygen is Sauerstoff (lit. sour substance), as is the Afrikaans word for oxygen suurstof, with the same meaning. English chemists, including Sir Humphry Davy, at the same time believed all acids contained hydrogen. Arrhenius used this belief to develop this definition of acid.
ब्रोन्स्टेड-लौरी: According to this definition, an acid is a proton (hydrogen nucleus) donor and a base is a proton acceptor. The acid is said to be dissociated after the proton is donated. An acid and the corresponding base are referred to as conjugate acid-base pairs. Brønsted and Lowry independently formulated this definition, which includes water-insoluble substances not in the Arrhenius definition. Acids according to this definition are variously referred to as Brønsted acids, Brønsted-Lowry acids, proton acids, protic acids, or protonic acids.
सल्भेण्ट-सिस्टम परिभाषा: According to this definition, an acid is a substance that, when dissolved in an autodissociating solvent, increases the concentration of the solvonium cations, such as H₃O⁺ in water, NH₄⁺ in liquid ammonia, NO⁺ in liquid N₂O₄, SbCl₂⁺ in SbCl₃, etc. Base is defined as the substance that increases the concentration of the solvate anions, respectively OH^-, NH₂^-, NO₃^-, or SbCl₄^-. This definition extends acid-base reactions to non-aqueous systems and even some aprotic systems, where no hydrogen nuclei are involved in the reactions. This definition is not absolute, a compound acting as acid in one solvent may act as a base in another.
लिवाइस: According to this definition developed by Gilbert N. Lewis, an acid is an electron-pair acceptor and a base is an electron-pair donor. (These are frequently referred to as "Lewis acids" and "Lewis bases," and are electrophiles and nucleophiles, respectively, in organic chemistry; Lewis bases are also ligands in coordination chemistry.) Lewis acids include substances with no transferable protons (ie H⁺ hydrogen ions), such as iron(III) chloride, and hence the Lewis definition of an acid has wider application than the Brønsted-Lowry definition. In fact, the term Lewis acid is often used to exclude protic (Brønsted-Lowry) acids. The Lewis definition can also be explained with molecular orbital theory. In general, an acid can receive an electron pair in its lowest unoccupied orbital (LUMO) from the highest occupied orbital (HOMO) of a base. That is, the HOMO from the base and the LUMO from the acid combine to a bonding molecular orbital.

दक्ले साधारण सिद्धान्त मजुसां ब्रोन्स्टेड-लौरी सिद्धान्त व परिभाषा दक्ले आपालं छ्य्‌लातःगु खने दु। अम्लया क्षमता, थ्व परिभाषा कथं, हाइड्रोनियमया स्टेबिलिटी व डिसोसियसनय् सोल्भेन्ट कञ्जुगेट बेसय् आधारित दु। कञ्जुगेट क्षारया अप्वइगु वा म्हो स्टेबिलिटीं कम्पाउण्डय् दैगु अप्व या म्हो अम्लीयतायात असर याइ। अम्लीयताया विचाः आपालं अर्‍ग्यानिक अम्ल दसु कार्बोक्जिलिक अम्लय् छ्येलिगु या। मोलेकुलर अर्बिटल परिभाषां (अन्-फिल्ड प्रोटोन अर्बाइटलं लोन पेयरयात ओभरल्याप याइगु विचा) लिवाइस परिभाषानाप स्वापू तः।

गुण

ब्रोन्स्टेड-लौरी अम्ल:

आपालं पाउंसे च्वंगु स्वाद दै
Strong or concentrated acids often produce a stinging feeling on mucous membranes
Change the color of pH indicators as follows: turn blue litmus and methyl orange red, turn phenolphthalein colorless
React with metals to produce a metal salt and hydrogen
React with metal carbonates to produce water, CO₂ and a salt
React with a base to produce a salt and water
React with a metal oxide to produce water and a salt
Conduct electricity, depending on the degree of dissociation
Produce solvonium ions, such as oxonium (H₃O⁺) ions in water

Acids are/can be gases, liquids, or solids. Respective examples (at 20 °C and 1 atm) are hydrogen chloride, sulfuric acid and citric acid. Solutions of acids in water are liquids, such as hydrochloric acid - an aqueous solution of hydrogen chloride. At 20 °C and 1 atm, linear carboxylic acids are liquids up to nonanoic acid (nine carbon atoms) and solids beginning from decanoic acid (ten carbon atoms). Aromatic carboxylic acids, the simplest being benzoic acid, are solids.

Strong acids and many concentrated acids, being corrosive, can be dangerous; causing severe burns for even minor contact. Generally, acid burns on the skin are treated by rinsing the affected area abundantly with running water, followed up with immediate medical attention. In the case of highly concentrated mineral acids such as sulfuric acid or nitric acid, the acid should first be wiped off, otherwise the exothermic mixing of the acid and the water could cause thermal burns.^{[पुष्टि(साइटेसन) मागु]} Particular acids may also be dangerous for reasons not related to their acidity. Material Safety Data Sheets (MSDS) can be consulted for detailed information on dangers and handling instructions.

नामाकरण

क्लासिकल नामाकरणय् अम्लतेत इमिगु एनायन कथं नां बियातै। That ionic suffix is dropped and replaced with a new suffix (and sometimes prefix), according to the table below. For example, HCl has chloride as its anion, so the -ide suffix makes it take the form hydrochloric acid. In the IUPAC naming system, "aqueous" is simply added to the name of the ionic compound. Thus, for hydrogen chloride, the IUPAC name would be aqueous hydrogen chloride. The prefix "hydro-" is added only if the acid is made up of just hydrogen and one other element.

क्लासिकल नामाकरण:

एनायन प्रिफिक्स	एनायन सफिक्स	अम्ल प्रिफिक्स	अम्ल सफिक्स	दसु
पर	एट	पर	इक अम्ल	परक्लोरिक अम्ल (HClO_४)
	एट		इक अम्ल	क्लोरिक अम्ल (HClO_३)
	आइट		ओस अम्ल	क्लोरस अम्ल (HClO_२)
हाइपो	आइट	हाइपो	अस अम्ल	हाइपोक्लोरस अम्ल (HClO)
	आइड	हाइड्रो	इक अम्ल	हाइड्रोक्लोरिक अम्ल (HCl)

रसायनिक गुण

In water the following equilibrium occurs between a weak acid (HA) and water, which acts as a base:

HA(aq) + H₂O ⇌ H₃O⁺(aq) + A^-(aq)

The acidity constant (or acid dissociation constant) is the equilibrium constant for the reaction of HA with water:

K_{a}={\frac {[{\mbox{H}}_{3}{\mbox{O}}^{+}][{\mbox{A}}^{-}]}{[{\mbox{HA}}]}}

Strong acids have large K_a values (i.e. the reaction equilibrium lies far to the right; the acid is almost completely dissociated to H₃O⁺ and A^-). Strong acids include the heavier hydrohalic acids: hydrochloric acid (HCl), hydrobromic acid (HBr), and hydroiodic acid (HI). (However, hydrofluoric acid, HF, is relatively weak.) For example, the K_a value for hydrochloric acid (HCl) is 10⁷.

Weak acids have small K_a values (i.e. at equilibrium significant amounts of HA and A⁻ exist together in solution; modest levels of H₃O⁺ are present; the acid is only partially dissociated). For example, the K_a value for acetic acid is 1.8 x 10^-5. Most organic acids are weak acids. Oxoacids, which tend to contain central atoms in high oxidation states surrounded by oxygen may be quite strong or weak. Nitric acid, sulfuric acid, and perchloric acid are all strong acids, whereas nitrous acid, sulfurous acid and hypochlorous acid are all weak.

Note on terms used:

The terms "hydrogen ion" and "proton" are used interchangeably; both refer to H⁺.
In aqueous solution, the water is protonated to form hydronium ion, H₃O⁺(aq). This is often abbreviated as H⁺(aq) even though the symbol is not chemically correct.
The strength of an acid is measured by its acid dissociation constant (K_a) or equivalently its pK_a (pK_a= - log(K_a)).
The pH of a solution is a measurement of the concentration of hydronium. This will depend on the concentration and nature of acids and bases in solution.

मोनोप्रोटिक अम्ल

मोनोप्रोटिक अम्ल थन्यागु अम्ल ख गुकिलिं केमिकल डिसोसियसन (वा आयोनाइजेसन)य् छगू अम्ल प्रति मोलेक्युल दान यायेफु। दसु (HAया चिं दुगु अम्ल स्वयादिसँ):

HA(aq) + H₂O(l) ⇌ H₃O⁺(aq) + A⁻(aq) K_a

थ्व कथंया अम्लया साधारण दसुलि खनिज अम्ल (गुकिलि हाइड्रोक्लोरिक अम्ल (HCl) व नाइट्रिक अम्ल (HNO_३) ला) ख। मेगु थासय् अर्‍ग्यानिक अम्लय् थ्व खँग्वः छगू कार्बोक्सिल पुचः दूगु अम्लया निंतिं छ्येलि गुकियात गबिलें-गबिलें मोनोकार्बोक्सिलिक अम्लया नां नं बिइगु या। दसुया अर्‍ग्यानिक अम्लय् फर्मिक अम्ल (HCOOH), एसेटिक अम्ल (CH_३COOH) व बेञ्जोइक अम्ल (C_६H_५COOH) ला।

पोलिप्रोटिक अम्ल

Polyprotic acids are able to donate more than one proton per acid molecule, in contrast to monoprotic acids that only donate one proton per molecule. Specific types of polyprotic acids have more specific names, such as diprotic acid (two potential protons to donate) and triprotic acid (three potential protons to donate).

A diprotic acid (here symbolized by H₂A) can undergo one or two dissociations depending on the pH. Each dissociation has its own dissociation constant, K_a1 and K_a2.

H₂A(aq) + H₂O(l) ⇌ H₃O⁺(aq) + HA⁻(aq) K_a1

HA⁻(aq) + H₂O(l) ⇌ H₃O⁺(aq) + A²⁻(aq) K_a2

The first dissociation constant is typically greater than the second; i.e., K_a1 > K_a2 . For example, sulfuric acid (H₂SO₄) can donate one proton to form the bisulfate anion (HSO₄⁻), for which K_a1 is very large; then it can donate a second proton to form the sulfate anion (SO₄²⁻), wherein the K_a2 is intermediate strength. The large K_a1 for the first dissociation makes sulfuric a strong acid. In a similar manner, the weak unstable carbonic acid (H₂CO₃) can lose one proton to form bicarbonate anion (HCO₃⁻) and lose a second to form carbonate anion (CO₃²⁻). Both K_a values are small, but K_a1 > K_a2 .

A triprotic acid (H₃A) can undergo one, two, or three dissociations and has three dissociation constants, where K_a1 > K_a2 > K_a3 .

H₃A(aq) + H₂O(l) ⇌ H₃O⁺(aq) + H₂A⁻(aq) K_a1

H₂A⁻(aq) + H₂O(l) ⇌ H₃O⁺(aq) + HA²⁻(aq) K_a2

HA²⁻(aq) + H₂O(l) ⇌ H₃O⁺(aq) + A³⁻(aq) K_a3

An inorganic example of a triprotic acid is orthophosphoric acid (H₃PO₄), usually just called phosphoric acid. All three protons can be successively lost to yield H₂PO₄⁻, then HPO₄²⁻, and finally PO₄³⁻ , the orthophosphate ion, usually just called phosphate. An organic example of a triprotic acid is citric acid, which can successively lose three protons to finally form the citrate ion. Even though the positions of the protons on the original molecule may be equivalent, the successive K_a values will differ since it is energetically less favorable to lose a proton if the conjugate base is more negatively charged.

न्युट्रलाइजेसन

Neutralization is the reaction between an acid and a base, producing a salt and neutralized base; for example, hydrochloric acid and sodium hydroxide form sodium chloride and water:

HCl(aq) + NaOH(aq) → H₂O(l) + NaCl(aq)

Neutralization is the basis of titration, where a pH indicator shows equivalence point when the equivalent number of moles of a base have been added to an acid. It is often wrongly assumed that neutralization should result in a solution with pH 7.0, which is only the case with similar acid and base strengths during a reaction.

Neutralization with a base weaker than the acid results in a weakly acidic salt. An example is the weakly acidic ammonium chloride, which is produced from the strong acid hydrogen chloride and the weak base ammonia. Conversely, neutralizing a weak acid with a strong base gives a weakly basic salt, e.g. sodium fluoride from hydrogen fluoride and sodium hydroxide.

कमजोर अम्ल/कमजोर क्षार समीकरण

मू पौ: हेण्डरसन-ह्यासेलब्याच समीकरण

In order to lose a proton, it is necessary that the pH of the system rise above the pK_a of the protonated acid. The decreased concentration of H⁺ in that basic solution shifts the equilibrium towards the conjugate base form (the deprotonated form of the acid). In lower-pH (more acidic) solutions, there is a high enough H⁺ concentration in the solution to cause the acid to remain in its protonated form, or to protonate its conjugate base (the deprotonated form).

Solutions of weak acids and salts of their conjugate bases form buffer solutions.

अम्लया छ्य्‌ला

अम्ल यक्व थासय् छ्य्‌लेछिं। अम्लयात आपालं खतं व मेमेगु धातुया करोजन (corrosion) लिकायेत पिक्लिङ प्रकृयाय् छ्येलि। अम्लयात वेट सेल ब्याट्रीइ इलेक्ट्रोलाइटया कथं नं छ्येलिगु या, दसु स्ल्फ्युरिक अम्लयात कार ब्याट्रीइ छ्यलि।

Strong acids, sulfuric acid in particular, are widely used in mineral processing. For example, phosphate minerals react with sulfuric acid to produce phosphoric acid for the production of phosphate fertilizers, and zinc is produced by dissolving zinc oxide into sulfuric acid, purifying the solution and electrowinning.

In the chemical industry, acids react in neutralization reactions to produce salts. For example, nitric acid reacts with ammonia to produce ammonium nitrate, a fertilizer. Additionally, carboxylic acids can be esterified with alcohols, to produce esters.

Acids are used as catalysts; for example, sulfuric acid is used in very large quantities in the alkylation process to produce gasoline. Strong acids, such as sulfuric, phosphoric and hydrochloric acids also effect dehydration and condensation reactions.

Acids are used as additives to drinks and foods, as they alter their taste and serve as preservatives. Phosphoric acid, for example, is a component of cola drinks.

जैविक स्थिति

मनु व यक्व मेमेगु प्राणीइ हाइड्रोक्लोरिक अम्ल ग्यास्ट्रिक अम्लया छगू भागया रुपं प्वाथं प्रोटिन व पोलिस्याकेराइड पाचनया निंतिं पिकाइ। थुकिलिं इन्-एक्टिभ प्रो-इञ्जाइम पेप्सिनोजेनयात इञ्जाइम पेप्सिनय् हिलाछ्वइ। छुं प्राणीतेसं अम्लयात प्रतिकारया निंतिं पिकाइ, दसु इमुं फर्मिक अम्ल पिकाइ।