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A device that converts the chemical energy obtained from a redox reaction * directly into electrical energy.

A device similar to a battery in which fuels such as hydrogen gas or methane can be combined directly with oxygen to produce electricity and very little heat.

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Hydrogen peroxide, H2O2, is a moderately strong oxidizing agent; it even

slowly oxidizes water. Its reactions tend to occur via radical paths, but it is

easy to understand the reactivity if you imagine the HOOH to split into OH-

and OH+; the OH+ would of course be the oxidizing agent, as it desperately

needs electrons. Its reactivity increases if the peroxy (OOH) part of the molecule

is linked to an electron withdrawing group, as in peroxyacids    !!!!

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   !!!!!

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METAMERISM, a technical term used in natural science. In chemistry it denotes the existence of different substances containing the same elements in the same proportions and having the same molecular weight; it is a form of isomerism.

In position isomerism, the basic carbon skeleton remains unchanged, but important groups are moved around on that skeleton.

For example, there are two structural isomers with the molecular formula C₃H₇Br. In one of them the bromine atom is on the end of the chain, whereas in the other it's attached in the middle.

                 !!!!!

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The first reaction step is nucleophilic addition of the base (for instance the hydroxide anion) to the carbonyl carbon of the aldehyde. The resulting alkoxide is deprotonated to give a di-anion, known as the Cannizzaro intermediate. Formation of this intermediate requires a strongly basic environment.

The mechanism of the Cannizzarro reaction

Both intermediates can react further with aldehyde to transfer a hydride, "H"−. The hydridic character of the C-H is enhanced by the electron-donating character of the alpha oxygen anion. This hydride transfer simultaneously generates an alkoxide anion (RCH2O-) and a carboxylic acid, which is rapidly deprotonated to form the carboxylate. Further evidence for the hydridic character of the Cannizzaro intermediate is provided by the formation of H2 by its reaction with water.

Only aldehydes that cannot form an enolate ion undergo the Cannizaro reaction. The aldehyde cannot have an enolizable proton. Under the basic conditions that facilitate the reaction, aldehydes that can form an enolate instead undergo aldol condensation. Examples of aldehydes that can undergo a Cannizzaro reaction include formaldehyde and aromatic aldehydes such as benzaldehyde    !!!!!

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Various effects have been distinguished in molecules in which electrons are displaced away from or towards a specified atom or group. The symbols used are as follows:

E – electromeric effect;

I – inductive effect (sometimes Is);

Id – inductomeric effect;

M – mesomeric effect;

R – resonance effect;

T – tautomeric effect, use mesomeric effect.

In addition, a plus sign before the symbol indicates that electron displacement is away from the atom or group (e.g. +I); a minus sign indicates displacement towards an atom or group (e.g. −I)   !!!!!

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Fermat's principle can be used to describe the properties

of light rays reflected off mirrors, refracted through different media,

or undergoing total internal reflection. It can be deduced from Huygens'

principle, and can be used to derive Snell's law of refraction and the

law of reflection.

The historical form of the French mathematician Pierre de Fermat is

incomplete. The modern, full version of Fermat's principle states that the

optical path length must be stationary, which means that it can be either

minimal, maximal or a point of inflection (a saddle point). Minima occur

when a wave passes from medium into another refraction and in the reflection

of light from a planar mirror. Maxima occur in gravitational lensing. A point of

inflection describes the path light takes when it is reflected off an elliptical

mirrored surface  !!!!

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    * Aluminium phosphate
* Calcium oxide
* Cyanuric chloride

* N,N'-Dicyclohexylcarbodiimide

* Iron(III) chloride

* Orthoformic acid
* Phosphorus pentoxide
* Phosphoryl chloride          !!!!!

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An acidic hydrogen atom is a hydrogen atom that has lost its electron and

is running around as a hydrogen ion. The lone proton (in 1H) has loaned out

its electron in a chemical reaction, like to chlorine in HCl, and when HCl is

combined with water, the H and the Cl separate into H+ and Cl- ions. That

H+ ion is the acidic hydrogen atom   !!!!

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Sn1 and sn2 reactions are nucleophilic substitution reactions in both the positive charged central species attract and forms a week electrostatic bonding.
If the bonding is very temporary and lasts very soon thats sn1 but if bonding is somewhat strong and both the species come together for a time together then all it's sn2 reaction.

Replace positive charge with negative and negative with positive will convert it into electrophilic substitution reaction only charge is the difference in most cases.
But some cases are very different and are subject of research.
That's all basic           !!!!!

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IUPAC nomenclature is a system of naming chemical compounds

and of describing the science of chemistry in general. It is developed

and kept up to date under the auspices of the International Union

of Pure and Applied Chemistry (IUPAC)   !!!!!

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In this case, it refrers to the very structured system we have for naming organisms so that related organisms are grouped together.
The advantage is it allows for understanding just what an organism is based on the name, what order, what class, etc...

There are thousands of ant species but one of the carpenter ants is called Camponotus atriceps   !!!!!

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epimer

A type of isomer in which the difference between the two compounds is the relative position of the H (hydrogen) group and OH (hydroxyl) group on the last asymmetric C (carbon) atom of the chain, as in the sugars D-glucose and D-mannose .

anomers

One of a pair of isomers of cyclic carbohydrates; resulting from creation of a new point of symmetry when a rearrangement of the atoms occurs at the aldehyde or ketone position !!!!

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Benzene, colorless liquid with a characteristic odor and burning taste, formula C6H6. The benzene molecule is a closed ring of six carbon atoms connected by bonds that resonate between single and double bonds; each carbon atom is also bound to a single hydrogen atom. It is insoluble in water, but miscible in all proportions with organic solvents. Benzene itself is an excellent solvent for certain elements, such as sulfur, phosphorus, and iodine; for gums, fats, waxes, and resins; and for most simple organic chemicals. It is one of the most commonly used solvents in the organic chemical laboratory. Benzene melts at 5.5° C (41.9° F), boils at 80.1° C (176.2° F), and has a specific gravity of 0.88 at 20° C (68° F). If inhaled in large quantities, benzene is poisonous. The vapors are explosive, and the liquid violently flammable. Many compounds, such as nitrobenzene, are obtained from benzene. Benzene is also used in the manufacture of drugs and in the production of important derivatives, such as aniline and phenol. Benzene and its derivatives are included in the important chemical group known as aromatic compounds 

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A weakened palladium catalyst called Lindlar's catalyst (Pd with CaCO3 and Pb(OAc)2 is very popular . With a weaker catalyst or much milder conditions, it is possible to reduce an alkene without reducing a carbonyl in the same molecule, even if they are conjugated !!!!

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Optical Isomerism

Two molecules are optical isomers of one another if they are

mirror images of one another, and
nonsuperimposible on one another

and Chiral compounds rotate plane polarized light. Each enantiomer will rotate the light in a different sense, clockwise or counterclockwise. Molecules that do this are said to be optically active  !!!!!

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Organic chemistry is a branch of chemistry that involves the study of organic carbon compounds. It encompasses the structures, composition, and synthesis of carbon-containing compounds. In understanding organic chemistry, it is important to note that all organic molecules consist not only of carbon, but also contain hydrogen. While it is true that organic compounds can contain other elements, the bond between carbon and hydrogen is what makes a compound organic    !!!!!!

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Rochelle salt (potassium sodium tartrate, NaKC₄H₄O₆)

it is a double salt used in Seidlitz powder; acts as a cathartic    !!!!!

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There is usually little need for alkanes to be synthesized in the laboratory, since they are usually commercially available. Also, alkanes are generally non-reactive chemically or biologically, and do not undergo functional group interconversions cleanly. When alkanes are produced in the laboratory, it is often a side-product of a reaction. For example, the use of n-butyllithium as a strong base gives the conjugate acid, n-butane as a side-product:

C4H9Li + H2O → C4H10 + LiOH

However, at times it may be desirable to make a portion of a molecule into an alkane like functionality (alkyl group) using the above or similar methods. For example, an ethyl group is an alkyl group; when this is attached to a hydroxy group, it gives ethanol, which is not an alkane. To do so, the best-known methods are hydrogenation of alkenes:

RCH=CH2 + H2 → RCH2CH3 (R = alkyl)

Alkanes or alkyl groups can also be prepared directly from alkyl halides in the Corey-House-Posner-Whitesides reaction. The Barton-McCombie deoxygenation removes hydroxyl groups from alcohols e.g.

    Barton-McCombie deoxygenation scheme

and the Clemmensen reduction removes carbonyl groups from aldehydes and ketones to form alkanes or alkyl-substituted compounds e.g.: