1.
Organic compound
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An organic compound is virtually any chemical compound that contains carbon, although a consensus definition remains elusive and likely arbitrary. Organic compounds are rare terrestrially, but of importance because all known life is based on organic compounds. The most basic petrochemicals are considered the building blocks of organic chemistry, for historical reasons discussed below, a few types of carbon-containing compounds, such as carbides, carbonates, simple oxides of carbon, and cyanides are considered inorganic. The distinction between organic and inorganic compounds, while useful in organizing the vast subject of chemistry. Organic chemistry is the science concerned with all aspects of organic compounds, Organic synthesis is the methodology of their preparation. The word organic is historical, dating to the 1st century, for many centuries, Western alchemists believed in vitalism. This is the theory that certain compounds could be synthesized only from their classical elements—earth, water, air, vitalism taught that these organic compounds were fundamentally different from the inorganic compounds that could be obtained from the elements by chemical manipulation. Vitalism survived for a while even after the rise of modern atomic theory and it first came under question in 1824, when Friedrich Wöhler synthesized oxalic acid, a compound known to occur only in living organisms, from cyanogen. A more decisive experiment was Wöhlers 1828 synthesis of urea from the inorganic salts potassium cyanate, urea had long been considered an organic compound, as it was known to occur only in the urine of living organisms. Wöhlers experiments were followed by others, in which increasingly complex organic substances were produced from inorganic ones without the involvement of any living organism. Even though vitalism has been discredited, scientific nomenclature retains the distinction between organic and inorganic compounds, still, even the broadest definition requires excluding alloys that contain carbon, including steel. The C-H definition excludes compounds that are considered organic, neither urea nor oxalic acid is organic by this definition, yet they were two key compounds in the vitalism debate. The IUPAC Blue Book on organic nomenclature specifically mentions urea and oxalic acid, other compounds lacking C-H bonds but traditionally considered organic include benzenehexol, mesoxalic acid, and carbon tetrachloride. Mellitic acid, which contains no C-H bonds, is considered an organic substance in Martian soil. The C-H bond-only rule also leads to somewhat arbitrary divisions in sets of carbon-fluorine compounds, for example, CF4 would be considered by this rule to be inorganic, whereas CF3H would be organic. Organic compounds may be classified in a variety of ways, one major distinction is between natural and synthetic compounds. Another distinction, based on the size of organic compounds, distinguishes between small molecules and polymers, natural compounds refer to those that are produced by plants or animals. Many of these are extracted from natural sources because they would be more expensive to produce artificially
2.
Ketone
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In chemistry, a ketone /ˈkiːtoʊn/ is an organic compound with the structure RCR, where R and R can be a variety of carbon-containing substituents. Ketones and aldehydes are simple compounds that contain a carbonyl group and they are considered simple because they do not have reactive groups like −OH or −Cl attached directly to the carbon atom in the carbonyl group, as in carboxylic acids containing −COOH. Many ketones are known and many are of importance in industry. Examples include many sugars and the industrial solvent acetone, which is the smallest ketone, the word ketone is derived from Aketon, an old German word for acetone. According to the rules of IUPAC nomenclature, ketones are named by changing the suffix -ane of the parent alkane to -anone, the position of the carbonyl group is usually denoted by a number. For the most important ketones, however, traditional names are still generally used. The common names of ketones are obtained by writing separately the names of the two alkyl groups attached to the group, followed by ketone as a separate word. The names of the groups are written alphabetically. When the two groups are the same, the prefix di- is added before the name of alkyl group. The positions of other groups are indicated by Greek letters, the α-carbon being the adjacent to carbonyl group. If both alkyl groups in a ketone are the same then the ketone is said to be symmetrical, although used infrequently, oxo is the IUPAC nomenclature for a ketone functional group. Other prefixes, however, are also used, for some common chemicals, keto or oxo refer to the ketone functional group. The term oxo is used widely through chemistry, for example, it also refers to an oxygen atom bonded to a transition metal. The ketone carbon is often described as sp2 hybridized, a description that includes both their electronic and molecular structure, ketones are trigonal planar around the ketonic carbon, with C−C−O and C−C−C bond angles of approximately 120°. Ketones differ from aldehydes in that the group is bonded to two carbons within a carbon skeleton. In aldehydes, the carbonyl is bonded to one carbon and one hydrogen and are located at the ends of carbon chains, ketones are also distinct from other carbonyl-containing functional groups, such as carboxylic acids, esters and amides. The carbonyl group is polar because the electronegativity of the oxygen is greater than that for carbon, thus, ketones are nucleophilic at oxygen and electrophilic at carbon. Because the carbonyl group interacts with water by bonding, ketones are typically more soluble in water than the related methylene compounds
3.
Aldehyde
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The group—without R—is the aldehyde group, also known as the formyl group. Aldehydes are common in organic chemistry, Aldehydes feature an sp2-hybridized, planar carbon center that is connected by a double bond to oxygen and a single bond to hydrogen. The C–H bond is not ordinarily acidic, because of resonance stabilization of the conjugate base, an α-hydrogen in an aldehyde is far more acidic, with a pKa near 15, compared to the acidity of a typical alkane. This acidification is attributed to the quality of the formyl center and the fact that the conjugate base. Related to, the group is somewhat polar. Aldehydes can exist in either the keto or the enol tautomer, keto-enol tautomerism is catalyzed by either acid or base. Usually the enol is the minority tautomer, but it is more reactive, the common names for aldehydes do not strictly follow official guidelines, such as those recommended by IUPAC, but these rules are useful. IUPAC prescribes the following nomenclature for aldehydes, Acyclic aliphatic aldehydes are named as derivatives of the longest carbon chain containing the aldehyde group, thus, HCHO is named as a derivative of methane, and CH3CH2CH2CHO is named as a derivative of butane. The name is formed by changing the suffix -e of the parent alkane to -al, so that HCHO is named methanal, in other cases, such as when a -CHO group is attached to a ring, the suffix -carbaldehyde may be used. Thus, C6H11CHO is known as cyclohexanecarbaldehyde, if the presence of another functional group demands the use of a suffix, the aldehyde group is named with the prefix formyl-. This prefix is preferred to methanoyl-, the word aldehyde was coined by Justus von Liebig as a contraction of the Latin alcohol dehydrogenatus. In the past, aldehydes were sometimes named after the corresponding alcohols, for example, the term formyl group is derived from the Latin word formica ant. This word can be recognized in the simplest aldehyde, formaldehyde, Aldehydes have properties that are diverse and that depend on the remainder of the molecule. Smaller aldehydes are more soluble in water, formaldehyde and acetaldehyde completely so, the volatile aldehydes have pungent odors. Aldehydes degrade in air via the process of autoxidation, the two aldehydes of greatest importance in industry, formaldehyde and acetaldehyde, have complicated behavior because of their tendency to oligomerize or polymerize. They also tend to hydrate, forming the geminal diol, the oligomers/polymers and the hydrates exist in equilibrium with the parent aldehyde. Aldehydes are readily identified by spectroscopic methods, using IR spectroscopy, they display a strong νCO band near 1700 cm−1. In their 1H NMR spectra, the formyl hydrogen center absorbs near δH =9 and this signal shows the characteristic coupling to any protons on the alpha carbon
4.
Functional group
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In organic chemistry, functional groups are specific groups of atoms or bonds within molecules that are responsible for the characteristic chemical reactions of those molecules. The same functional group will undergo the same or similar chemical reaction regardless of the size of the molecule it is a part of, however, its relative reactivity can be modified by other functional groups nearby. The atoms of functional groups are linked to other and to the rest of the molecule by covalent bonds. Any subgroup of atoms of a compound also may be called a radical, and if a covalent bond is broken homolytically, Functional groups can also be charged, e. g. in carboxylate salts, which turns the molecule into a polyatomic ion or a complex ion. Complexation and solvation is also caused by interactions of functional groups. In the common rule of thumb like dissolves like, it is the shared or mutually well-interacting functional groups give rise to solubility. For example, sugar dissolves in water because both share the functional group and hydroxyls interact strongly with each other. Combining the names of groups with the names of the parent alkanes generates what is termed a systematic nomenclature for naming organic compounds. In traditional nomenclature, the first carbon atom after the carbon that attaches to the group is called the alpha carbon, the second, beta carbon. IUPAC conventions call for numeric labeling of the position, e. g. 4-aminobutanoic acid, in traditional names various qualifiers are used to label isomers, for example isopropanol is an isomer is n-propanol. The following is a list of functional groups. In the formulas, the symbols R and R usually denote an attached hydrogen, or a side chain of any length. Functional groups, called hydrocarbyl, that only carbon and hydrogen. Each one differs in type of reactivity, there are also a large number of branched or ring alkanes that have specific names, e. g. tert-butyl, bornyl, cyclohexyl, etc. Hydrocarbons may form charged structures, positively charged carbocations or negative carbanions, examples are tropylium and triphenylmethyl cations and the cyclopentadienyl anion. Haloalkanes are a class of molecule that is defined by a carbon–halogen bond and this bond can be relatively weak or quite stable. In general, with the exception of fluorinated compounds, haloalkanes readily undergo nucleophilic substitution reactions or elimination reactions, the substitution on the carbon, the acidity of an adjacent proton, the solvent conditions, etc. all can influence the outcome of the reactivity. Compounds that contain nitrogen in this category may contain C-O bonds, compounds that contain sulfur exhibit unique chemistry due to their ability to form more bonds than oxygen, their lighter analogue on the periodic table
5.
Dinitrophenylhydrazine
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2, 4-Dinitrophenylhydrazine is the chemical compound C6H32NHNH2. Dinitrophenylhydrazine is a red to orange solid and it is a substituted hydrazine, and is often used to qualitatively test for carbonyl groups associated with aldehydes and ketones. The hydrazone derivatives can also be used as evidence toward the identity of the original compound, the melting point of the derivative is often used, with reference to a database of values, to determine the identity of a specific carbonyl compound. It is relatively sensitive to shock and friction, it is a shock explosive so care must be taken with its use, to reduce its explosive hazard, it is usually supplied wet. 2, 4-Dinitrophenylhydrazine is commercially available usually as a wet powder,2, 4-Dinitrophenylhydrazine can be used to qualitatively detect the carbonyl functionality of a ketone or aldehyde functional group. It is also considered a reaction, nucleophilic addition of the -NH2 group to the C=O carbonyl group. In particular, the use of 2, 4-dinitrophenylhydrazine was developed by Brady, modern spectroscopic and spectrometric techniques have since superseded these techniques. Dinitrophenylhydrazine does not react with other carbonyl-containing functional groups such as acids, amides. This stability would be lost by addition of a reagent to the carbonyl group, hence, these compounds are more resistant to addition reactions. Also with carboxylic acids there is the effect of the acting as a base. Tollens reagent Fehlings reagent Schiff test
6.
Sorbent
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A sorbent is a material used to absorb or adsorb liquids or gases. Examples include, A material similar to molecular sieve material, which acts by adsorption and it has a large internal surface area and good thermal conductivity. It is typically supplied in pellets of 1 mm to 2 mm diameter, occasionally as beads up to 5 mm diameter. They are typically made from aluminium oxide with a porous structure, materials used to absorb other materials due to their high affinity for doing so. Examples include, In composting, dry materials absorb many odoriferous chemicals, a sponge absorbs many times its own weight in water. A polypropylene fiber mat may be used to absorb oil, a cellulose fiber product may be used to absorb oil. The granular gel material in a baby diaper will absorb several times its weight in urine. Polymethylsiloxane polyhydrate is a gelly-like polymeric organosilicon compound, PMSPG is an sorbent designed for binding toxic substances of different nature, pathogens and metabolites in the gastrointestinal tract and their excretion. Desiccants absorb water, drying out the surrounding materials
7.
Adsorption
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Adsorption is the adhesion of atoms, ions, or molecules from a gas, liquid, or dissolved solid to a surface. This process creates a film of the adsorbate on the surface of the adsorbent and this process differs from absorption, in which a fluid is dissolved by or permeates a liquid or solid, respectively. Adsorption is a process while absorption involves the whole volume of the material. The term sorption encompasses both processes, while desorption is the reverse of it, similar to surface tension, adsorption is a consequence of surface energy. In a bulk material, all the requirements of the constituent atoms of the material are filled by other atoms in the material. However, atoms on the surface of the adsorbent are not wholly surrounded by other adsorbent atoms, the exact nature of the bonding depends on the details of the species involved, but the adsorption process is generally classified as physisorption or chemisorption. It may also occur due to electrostatic attraction, pharmaceutical industry applications, which use adsorption as a means to prolong neurological exposure to specific drugs or parts thereof, are lesser known. The word adsorption was coined in 1881 by German physicist Heinrich Kayser, adsorption is usually described through isotherms, that is, the amount of adsorbate on the adsorbent as a function of its pressure or concentration at constant temperature. The quantity adsorbed is nearly always normalized by the mass of the adsorbent to allow comparison of different materials, to date,15 different isothem models were developed. The function is not adequate at very high pressure because in reality x / m has a maximum as pressure increases without bound. As the temperature increases, the k and n change to reflect the empirical observation that the quantity adsorbed rises more slowly. Irving Langmuir was the first to derive a scientifically based adsorption isotherm in 1918, the model applies to gases adsorbed on solid surfaces. It is a semi-empirical isotherm with a basis and was derived based on statistical thermodynamics. It is the most common isotherm equation to use due to its simplicity and it is based on four assumptions, All of the adsorption sites are equivalent and each site can only accommodate one molecule. The surface is energetically homogeneous and adsorbed molecules do not interact, at the maximum adsorption, only a monolayer is formed. Adsorption only occurs on localized sites on the surface, not with other adsorbates, the fourth condition is the most troublesome, as frequently more molecules will adsorb to the monolayer, this problem is addressed by the BET isotherm for relatively flat surfaces. The Langmuir isotherm is nonetheless the first choice for most models of adsorption, Langmuir suggested that adsorption takes place through this mechanism, A g + S ⇌ A S, where A is a gas molecule and S is an adsorption site. The direct and inverse rate constants are k and k−1, vmon is related to the number of adsorption sites through the ideal gas law
8.
High-performance liquid chromatography
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High-performance liquid chromatography, is a technique in analytical chemistry used to separate, identify, and quantify each component in a mixture. It relies on pumps to pass a pressurized liquid solvent containing the mixture through a column filled with a solid adsorbent material. HPLC has been used for manufacturing, legal, research, Chromatography can be described as a mass transfer process involving adsorption. HPLC relies on pumps to pass a pressurized liquid and a sample mixture through a column filled with adsorbent, the active component of the column, the adsorbent, is typically a granular material made of solid particles, 2–50 micrometers in size. The components of the mixture are separated from each other due to their different degrees of interaction with the adsorbent particles. The pressurized liquid is typically a mixture of solvents and is referred to as a mobile phase and its composition and temperature play a major role in the separation process by influencing the interactions taking place between sample components and adsorbent. These interactions are physical in nature, such as hydrophobic, dipole–dipole and ionic, due to the small sample amount separated in analytical HPLC, typical column dimensions are 2. 1–4.6 mm diameter, and 30–250 mm length. Also HPLC columns are made with smaller sorbent particles and this gives HPLC superior resolving power when separating mixtures, which makes it a popular chromatographic technique. The schematic of an HPLC instrument typically includes a sampler, pumps, the sampler brings the sample mixture into the mobile phase stream which carries it into the column. The pumps deliver the flow and composition of the mobile phase through the column. The detector generates a signal proportional to the amount of sample component emerging from the column, a digital microprocessor and user software control the HPLC instrument and provide data analysis. Some models of pumps in a HPLC instrument can mix multiple solvents together in ratios changing in time. Various detectors are in use, such as UV/Vis, photodiode array or based on mass spectrometry. Most HPLC instruments also have an oven that allows for adjusting the temperature at which the separation is performed. The sample mixture to be separated and analyzed is introduced, in a small volume. The components of the move through the column at different velocities. The velocity of each component depends on its nature, on the nature of the stationary phase. The time at which an analyte elutes is called its retention time
