Hydrolysis

Hydrolysis is a chemical reaction or process in which a chemical compound is broken down by reaction with water. A chemical reaction is a process that always results in the interconversion of Chemical substances The substance or substances initially involved in a chemical reaction are called A chemical compound is a substance consisting of two or more different elements chemically bonded together in a fixed proportion by Mass. Water ( H2[[oxygen O]] H OH) is the most abundant Molecule on Earth 's surface composing of about 70% of the Earth's surface as ^[1]^[2] It is the type of reaction that is used to break down certain polymers, especially those made by step-growth polymerization. A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Step-growth polymerization is a Polymerization process that involves a Chemical reaction between multifunctional Monomer molecules Such polymer degradation is usually catalysed by either acid or alkali, attack often increasing with strength or pH. Polymer degradation is a change in the properties - Tensile strength, Colour, shape etc - of a Polymer or polymer based product under the influence of In Computer science, ACID ( Atomicity Consistency Isolation Durability) is a set of properties that guarantee that Database transactions are In Chemistry, an alkali (from Arabic: Al-Qaly القلي القالي) is a basic, ionic salt of an Alkali metal pH is the measure of the acidity or alkalinity of a Solution.

1 Types
2 Hydrolysis of amide links
3 Hydrolysis of metal salts
4 Hydrolysis of cellulose (Cellulolysis)
5 Irreversibility of hydrolysis under physiological conditions
6 See also
7 References
8 External links

Types

In organic chemistry, hydrolysis can be considered as the reverse or opposite of condensation, a reaction in which two molecular fragments are joined for each water molecule produced. Organic chemistry is a discipline within Chemistry which involves the scientific study of the structure properties composition reactions, and preparation A condensation reaction is a Chemical reaction in which two Molecules or moieties ( Functional groups) combine to form one single molecule together with As hydrolysis may be a reversible reaction, condensation and hydrolysis can take place at the same time, with the position of equilibrium determining the amount of each product.

In inorganic chemistry, the word is often applied to solutions of salts and the reactions by which they are converted to new ionic species or to precipitates (oxides, hydroxides, or salts). Inorganic chemistry is the branch of Chemistry concerned with the properties and behavior of Inorganic compounds This field covers all Chemical compounds The addition of a molecule of water to a chemical compound, without forming any other products is usually known as hydration, rather than hydrolysis. In Organic chemistry, a hydration reaction is a Chemical reaction in which a Hydroxyl group (OH- and a Hydrogen Cation

In biochemistry, hydrolysis is considered the reverse or opposite of dehydration synthesis. Biochemistry is the study of the chemical processes in living Organisms It deals with the Structure and function of cellular components such as A condensation reaction is a Chemical reaction in which two Molecules or moieties ( Functional groups) combine to form one single molecule together with In hydrolysis, a water molecule (H₂O), is added, whereas in dehydration synthesis, a molecule of water is removed.

In electrochemistry, hydrolysis can also refer to the electrolysis of water. Electrochemistry is a branch of Chemistry that studies Chemical reactions which take place in a Solution at the interface of an electron conductor Electrolysis of water is the decomposition of Water (H2O into Oxygen (O2 and Hydrogen gas (H2 In hydrolysis, a voltage is applied across an aqueous medium, which produces a current and breaks the water into its constituents, hydrogen and oxygen.

In polymer chemistry, hydrolysis of polymers can occur during high-temperature processing such as injection moulding leading to chain degradation and loss of product integrity. Polymer chemistry or macromolecular chemistry is a multidisciplinary Science that deals with the Chemical synthesis and chemical properties of A polymer is a large Molecule ( Macromolecule) composed of repeating Structural units typically connected by Covalent Chemical bonds Injection molding (British moulding Polymers most at risk include PET, polycarbonate, nylon and other polymers made by step-growth polymerization. A pet is an Animal kept for companionship and enjoyment or a househeld animal as opposed to Livestock, Laboratory animals Working animals Overview Nylon is a Thermoplastic silky material first used commercially in a nylon- Bristled Toothbrush (1938 followed more famously by Step-growth polymerization is a Polymerization process that involves a Chemical reaction between multifunctional Monomer molecules Such materials must be dried prior to moulding.

Hydrolysis of amide links

In other hydrolysis reactions, such as hydrolysis of an amide link into a carboxylic acid and an amine product or ammonia, only the carboxylic acid product has a hydroxyl group derived from the water. In Chemistry, an amide is one of three kinds of Compounds (sometimes called acid amide the organic Functional group characterized Carboxylic acids are Organic acids characterized by the presence of a Carboxyl group, which has the formula -C(=OOH usually written -COOH or -CO2H Amines are Organic compounds and Functional groups that contain a basic Nitrogen Atom with a Lone pair. Ammonia is a compound with the formula N[[hydrogen H3]] It is normally encountered as a Gas with a characteristic pungent Odor The amine product (or ammonia) gains the remaining hydrogen ion. A more specific case of the hydrolysis of an amide link is hydrolyzing the peptide links of amino acids. A peptide bond is a Chemical bond formed between two Molecules when the Carboxyl group of one molecule reacts with the In Chemistry, an amino acid is a Molecule containing both Amine and Carboxyl Functional groups In Biochemistry, this

Many polyamide polymers such as nylon 6,6 are attacked and hydrolysed by strong acids. A polyamide is a Polymer containing Monomers of Amides joined by Peptide bonds They can occur both naturally examples being Proteins Nylon 6-6, also referred to as nylon 66, is a type of nylon Nylon comes in many types the two most common for textile and plastics industries are Nylon 6 and Such attack leads to depolymerization and nylon products fail by fracturing when exposed to even small amounts of acid. In Polymer chemistry, polymerization is a process of reacting Monomer Molecules together in a Chemical reaction to form three-dimensional networks The reaction is essentially the reverse of the synthesis from monomers:

Other polymers made by step-growth polymerization are susceptible to similar polymer degradation reactions. Step-growth polymerization is a Polymerization process that involves a Chemical reaction between multifunctional Monomer molecules Polymer degradation is a change in the properties - Tensile strength, Colour, shape etc - of a Polymer or polymer based product under the influence of The problem is known as stress corrosion cracking. Fracture mechanics --> Stress corrosion cracking ( SCC) is the unexpected sudden failure of normally Ductile metals or tough Thermoplastics

Hydrolysis of metal salts

(As noted above, hydrolysis of metal salts is more commonly known as hydration. ) Many metal ions are strong Lewis acids, and in water they may undergo hydrolysis to form basic salts. Such salts contain a hydroxyl group that is directly bound to the metal ion in place of a water ligand. Hydroxyl in Chemistry stands for a molecule consisting of an Oxygen atom and a Hydrogen atom connected by a Covalent bond. In Chemistry, a ligand is either an Atom, Ion, or Molecule (see also Functional group) that bonds to a central metal generally The positive charge on metal ions creates an attraction to water, a Lewis base with a non-binding electron pair on the oxygen atom, and alters water's electron density. Oxygen (from the Greek roots ὀξύς (oxys (acid literally "sharp" from the taste of acids and -γενής (-genēs (producer literally begetteris the This in turn increases the polarity of the O-H bond, which now acts as a proton donor under Brønsted-Lowry acid-base theory to release the hydrogen as a H+ ion, increasing the acidity of the solution. "Polar molecule" and "Non-polar" redirect here For example, aluminium chloride undergoes extensive hydrolysis in water such that the solution becomes very acidic. Aluminium chloride (AlCl3 is a compound of Aluminium and Chlorine.

$[Al(H_2 O)_6]^{3+} \underset{\ H_3 O^+}{\overset{H_2 O}{\rightleftharpoons}} [Al(OH)(H_2 O)_5]^{2+}$

This implies that hydrogen chloride is lost in the evaporation of AlCl₃ solutions and the residue is a basic salt (in this case an oxychloride) in place of AlCl₃. Such behaviour is also seen with other metal chlorides such as ZnCl₂, SnCl₂, FeCl₃ and lanthanide halides such as DyCl₃. Zinc chloride is the name of Chemical compound with the formula Zn[[chlorine Cl]]2 and its hydrates Tin(II chloride (stannous chloride is a white Crystalline solid with the formula 2 Iron chloride redirects here For Iron(II chloride see Iron(II chloride. Dysprosium(III chloride (DyCl3 also known as dysprosium trichloride, is a compound of Dysprosium and Chlorine. With some compounds such as TiCl₄, the hydrolysis may go to completion and form the pure hydroxide or oxide, in this case TiO₂. Titanium tetrachloride or titanium(IV chloride is the Chemical compound with the formula TiCl4 In Chemistry, hydroxide is the most common name for the diatomic Anion OH− consisting of Oxygen and Hydrogen An oxide is a Chemical compound containing at least one Oxygen atom as well as at least one other element Titanium dioxide, also known as titanium(IV oxide or titania, is the naturally occurring Oxide of Titanium, chemical formula Ti[[oxygen

Hydrolysis of cellulose (Cellulolysis)

Main article: Cellulase

Cellulolytic is relating to or causing the hydrolysis of cellulose (i. Cellulase refers to a class of Enzymes produced chiefly by Fungi, Bacteria, and Protozoans that Catalyze the cellulolysis (or Cellulose is an Organic compound with the formula, a Polysaccharide consisting of a linear chain of several hundred to over ten thousand β(1→4 e. cellulolytic bacteria, fungi or enzymes). The Bacteria ( singular: bacterium) are a large group of unicellular Microorganisms Typically a few Micrometres in length bacteria have A fungus (ˈfʌŋgəs is a eukaryotic Organism that is a member of the kingdom Fungi (ˈfʌndʒaɪ Enzymes are Biomolecules that catalyze ( ie increase the rates of Chemical reactions Almost all enzymes are Proteins

The hydrolysis into glucose (i. e. of cellulose or starch) is called saccharification.

Irreversibility of hydrolysis under physiological conditions

Under physiological conditions (i. e. in dilute aqueous solution), a hydrolytic cleavage reaction, where the concentration of a metabolic precursor is low (on the order of 10^-3 to 10^-6 molar), is essentially thermodynamically irreversible. In Physics, thermodynamics (from the Greek θερμη therme meaning " Heat " and δυναμις dynamis meaning " To give an example:

A + H₂O → X + Y

$K_d = \frac{\left[X\right] \left[Y\right]} {\left[H_2O\right] \left[A\right]}$

Assuming that x is the final concentration of products, and that C is the initial concentration of A, and W = [H₂O] = 55. 5 molar, then x can be calculated with the equation:

$\frac{x \times x}{W\left(C - x\right)} = K_d$

let K_d×W = k:

then $x = \frac {-k + \sqrt {k^2 + 4kC} } {2}.$

For a value of C = 0. 001 molar, and k = 1 molar, x/C > 0. 999. Less than 0. 1% of the original reactant would be present once the reaction is complete.

This theme of physiological irreversibility of hydrolysis is used consistently in metabolic pathways, since many biological processes are driven by the cleavage of anhydrous pyrophosphate bonds. In Chemistry, an anhydride is a compound that can be considered as derived from another compound by subtracting the molecules of water. In Chemistry, the Anion, the Salts and the Esters of Pyrophosphoric acid are called pyrophosphates.

References

^ Compendium of Chemical Terminology, hydrolysis, accessed 2007-01-23. Adenosine-5'-triphosphate ( ATP) is a multifunctional Nucleotide that is most important as a " molecular currency" of intracellular Energy A condensation reaction is a Chemical reaction in which two Molecules or moieties ( Functional groups) combine to form one single molecule together with Polymer degradation is a change in the properties - Tensile strength, Colour, shape etc - of a Polymer or polymer based product under the influence of Solvolysis is a special type of Nucleophilic substitution or elimination where the Nucleophile is a Solvent molecule Compendium of Chemical Terminology (ISBN 0-86542-684-8 is a book published by IUPAC containing internationally accepted definitions for terms in Chemistry. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 393 - Roman Emperor Theodosius I proclaims his nine year old son Honorius co-emperor
^ Compendium of Chemical Terminology, solvolysis, accessed 2007-01-23. Compendium of Chemical Terminology (ISBN 0-86542-684-8 is a book published by IUPAC containing internationally accepted definitions for terms in Chemistry. Year 2007 ( MMVII) was a Common year starting on Monday of the Gregorian calendar in the 21st century. Events 393 - Roman Emperor Theodosius I proclaims his nine year old son Honorius co-emperor

External links

Dictionary

-noun

(chemistry) A chemical process of decomposition involving the splitting of a bond and the addition of the hydrogen cation and the hydroxide anion of water.
(biochemistry) The degradation of certain biopolymers (proteins, complex sugars) by the chemical process that results in smaller polymers or monomers (such as amino acids or monosaccharides)

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