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| {{Distinguish|Imide}}
| | These are only a limited of numerous categories folks are put into based on their fat. So how do you know where you fit? There are virtually hundreds of charts to measure by, sow which one functions best?<br><br>If most of the population is overweight (according to the [http://safedietplans.com/bmi-chart bmi chart]) the error inside logic might be which the population is right and the bmi chart is incorrect.<br><br>What have you just performed bmi chart men mathematically? We've doubled each dimension. In the task of doing which, we've octupled the amount of bricks plus octupled the volume of the bricks. The 8 is 2 raised to the third power.<br><br>The body is about 60% water. Normally we should drink 2.4 liters (81.15 ounces) of water each day thus that the body could function correctly according to the U.S. Geology Survey (USGS) Water Resources for the United States. When losing weight you need to drink 64 ounces of water per pound of lean body mass. Which means we will need to double that amount if you're physically active or overweight (as much as 128 oz. if you're 200lbs.) As reported by the Mayo Clinic, The Institute of Medicine advises which men consume roughly 3 liters (regarding 13 cups) of total beverages a day and women consume 2.2 liters (regarding 9 cups) of total beverages a day.<br><br>Lets begin with an ordinary brick, like the multi-colored 1 at proper. We like to create a tiny brick pile that has the same proportions as the initially brick, however is twice because big in every 3 dimensions. First you add a brick, in purchase to double the length. Then alongside that, we add two more bricks to double the width.<br><br>More direct evidence showing the guy needs is studies where subjects have been rating images of real persons. Men found in bmi chart women this form of research which women with ratio of .70 to .71 were more attractive than ladies with ratio of .73 to .74 (Rempala & Garvey, 2007). Similar finding has been found inside many studies. As an example it was found that not only do guys like a Waits-to-Hip ratio about .7, but they also have a strong, non-linear, preference based on female BMI (Body mass index). The many desirable bodies had Waist-to-Hip ratio around the ideal range of .7, nevertheless the desirability was dependent on BMI (Tovee et al, 1999).<br><br>34.Speed at 40/Beating your PR:There have been many articles regarding how ladies are older ladies are getting faster plus staying there (see ABC News article on Yale University Study). As you gain experience, you become better runners. We know to run the tangents, prepare correctly, and read strategies like numerous you have indexed here. We furthermore have more time to train as our kids get older.<br><br>Then, how can you go from finding the online BMI chart? A variety of time-tested exercise routines for fat reduction are accessible online. You'll be able to receive began inside real time. |
| {{Use dmy dates|date=July 2012}}
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| [[File:AmideTypes.png|thumb|320px|Structures of three kinds of amides: an organic amide, a sulfonamide, and a phosphoramide.]]
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| An '''amide''', also known as an [[Fatty_acid_amide|'-acid amide']], is a compound with the functional group R<sub>n</sub>E(O)<sub>x</sub>NR'<sub>2</sub> (R and R' refer to H or organic groups). Most common are "organic amides" (n = 1, E = C, x = 1), but many other important types of amides are known including phosphor amides (n = 2, E = P, x = 1 and many related formulas) and [[Sulfonamide (chemistry)|sulfonamide]]s (E = S, x= 2).<ref>{{goldbookref|file=A00266|title=amides}}</ref> The term amide refers both to ''classes of compounds'' and to the ''[[functional group]]'' (R<sub>n</sub>E(O)<sub>x</sub>NR'<sub>2</sub>) within those compounds.
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| Amide can ''also'' refer to the [[conjugate base]] of [[ammonia]] (the anion H<sub>2</sub>N<sup>−</sup>) or of an organic [[amine]] (an anion R<sub>2</sub>N<sup>−</sup>). For discussion of these "[[anionic]] amides", see [[Metal amides#Alkali metal amides]].
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| The remainder of this article is about the [[carbonyl]]-[[nitrogen]] sense of ''amide''.
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| ==Structure and bonding==
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| The simplest amides are derivatives of ammonia wherein one hydrogen atom has been replaced by an [[acyl]] group. The ensemble is generally represented as RC(O)NH<sub>2</sub>. Closely related and even more numerous are amides derived from primary amines (R'NH<sub>2</sub>) with the formula RC(O)NHR'. Amides are also commonly derived from [[secondary amine]]s (R'R<nowiki>''</nowiki>NH) with the formula RC(O)NR'R<nowiki>''</nowiki>. Amide are usually regarded as derivatives of [[carboxylic acid]]s in which the [[hydroxyl]] group has been replaced by an amine or ammonia.
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| :[[Image:AmideResonance.png|300px|Amide resonance:]]
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| The lone pair of [[electron]]s on the [[nitrogen]] is delocalized into the carbonyl, thus forming a partial [[double bond]] between N and the [[carbonyl]] [[carbon]]. Consequently the nitrogen in amides is not pyramidal. It is estimated that acetamide is described by [[resonance structure]] A for 62% and by B for 28%<ref name = Kemnitz>{{Cite journal|doi=10.1021/ja0663024|title="Amide Resonance" Correlates with a Breadth of C−N Rotation Barriers|year=2007|last1=Kemnitz|first1=Carl R.|last2=Loewen|first2=Mark J.|journal=Journal of the American Chemical Society|volume=129|issue=9|pages=2521–8|pmid=17295481}}</ref>
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| <!--needs:
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| barrier from DMF, and a more general ref than this JACS rpt
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| comment on syn and anti secondary amides-->
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| [[Image:Formamide-MO-3D-balls.png|thumb|right|180px|Amides possess a [[conjugated system]] spread over the O, C and N atoms, consisting of [[molecular orbital]]s occupied by [[delocalized electron]]s. One of the [[pi bond|''π'' molecular orbitals]] in [[formamide]] is shown above.]]
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| ==Nomenclature==
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| {{Main|IUPAC nomenclature of organic chemistry#Amines and amides}}
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| In the usual nomenclature, one adds the term "amide" to the stem of the parent acid's name. For instance, the amide derived from [[acetic acid]] is named [[acetamide]] (CH<sub>3</sub>CONH<sub>2</sub>). IUPAC recommends [[ethanamide]], but this and related formal names are rarely encountered. When the amide is derived from a primary or secondary amine, the substitutents on nitrogen are indicated first in the name. Thus, the amide formed from [[dimethylamine]] and [[acetic acid]] is ''N,N''-dimethylacetamide (CH<sub>3</sub>CONMe<sub>2</sub>, where Me = CH<sub>3</sub>). Usually even this name is simplified to [[dimethylacetamide]]. Cyclic amides are called [[lactam]]s; they are necessarily secondary or tertiary amides. Functional groups consisting of -P(O)NR<sub>2</sub> and -SO<sub>2</sub>NR<sub>2</sub> are [[phosphonamides]] and [[sulfonamide (chemistry)|sulfonamide]]s, respectively.<ref>Organic Chemistry IUPAC Gnomenclature. Rules C-821. Amides http://www.acdlabs.com/iupac/nomenclature/79/r79_540.htm</ref> | |
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| ===Pronunciation===
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| Some chemists make a pronunciation distinction between the two, saying {{IPAc-en|ə|ˈ|m|iː|d}} for the [[carbonyl]]-[[nitrogen]] compound and {{IPAc-en|audio=En-uk-amide.ogg|ˈ|æ|m|aɪ|d}} {{contradict-inline|date=August 2012}} for the [[anion]]. Others substitute one of these with {{IPAc-en|ˈ|æ|m|ɨ|d}}, while still others pronounce both {{IPAc-en|ˈ|æ|m|ɨ|d}}, making them [[homonym]]s.
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| ==Properties==
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| ===Basicity===
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| Compared to [[amine]]s, amides are very weak [[Base (chemistry)|base]]s. While the [[conjugate acid]] of an [[amine]] has a [[pKa]] of about 9.5, the [[conjugate acid]] of an amide has a pKa around −0.5. Therefore amides don't have as clearly noticeable [[acid-base]] properties in [[water]]. This relative lack of basicity is explained by the [[electron]]-withdrawing nature of the [[carbonyl group]] where the lone pair of [[electron]]s on the [[nitrogen]] is delocalized by [[resonance (chemistry)|resonance]]. On the other hand, amides are much stronger [[Base (chemistry)|base]]s than [[carboxylic acid]]s, [[ester]]s, [[aldehyde]]s, and [[ketone]]s (conjugated acid pKa between −6 and −10). It is estimated [[in silico]] that [[acetamide]] is represented by [[resonance structure]] A for 62% and by B for 28%.<ref name = Kemnitz/> Resonance is largely prevented in the very strained [[quinuclidone]].
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| Because of the greater electronegativity of oxygen, the carbonyl (C=O) is a stronger dipole than the N–C dipole. The presence of a C=O dipole and, to a lesser extent a N–C dipole, allows amides to act as H-bond acceptors. In primary and secondary amides, the presence of N–H dipoles allows amides to function as H-bond donors as well. Thus amides can participate in hydrogen bonding with water and other protic solvents; the oxygen atom can accept hydrogen bonds from water and the N–H hydrogen atoms can donate H-bonds. As a result of interactions such as these, the water solubility of amides is greater than that of corresponding hydrocarbons.
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| The proton of a primary or secondary amide does not dissociate readily under normal conditions; its p''K<sub>a</sub>'' is usually well above 15. Conversely, under extremely acidic conditions, the carbonyl [[oxygen]] can become protonated with a p''K<sub>a</sub>'' of roughly −1.
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| ===Solubility===
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| The solubilities of amides and esters are roughly comparable. Typically amides are less soluble than comparable amines and carboxylic acids since these compounds can both donate and accept hydrogen bonds. Tertiary amides, with the important exception of N,N-dimethylformamide, exhibit low solubility in water.
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| ==Characterization==
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| The presence of the functional group is generally easily established, at least in small molecules. They are the most common non-basic functional group. They can be distinguished from nitro and cyano groups by their [[IR spectroscopy|IR spectra]]. Amides exhibit a moderately intense ν<sub>CO</sub> band near 1650 cm<sup>−1</sup>. By <sup>1</sup>H [[NMR spectroscopy]], CON''H''R signals occur at low fields. In X-ray crystallography, the C(O)N center together with the three immediately adjacent atoms characteristically define a plane.
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| ==Applications and occurrence==
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| Amides are pervasive in nature and technology as structural materials. The amide linkage is easily formed, confers structural rigidity, and resists [[hydrolysis]]. Nylons are polyamides, as are the very resilient materials [[Aramid]], [[Twaron]], and [[Kevlar]]. Amide linkages constitute a defining molecular feature of [[protein]]s, the [[secondary structure]] of which is due in part to the [[hydrogen bonding]] abilities of amides. Amide linkages in a [[biochemistry|biochemical]] context are called [[peptide bond]]s when they occur in the main chain of a protein and [[isopeptide bond]]s when they occur to a side-chain of the protein. Proteins can have structural roles, such as in [[hair]] or [[spider silk]], but also nearly all [[enzyme]]s are proteins. Low molecular weight amides, such as [[dimethylformamide]] (HC(O)N(CH<sub>3</sub>)<sub>2</sub>), are common solvents. Many drugs are amides, including [[penicillin]] and [[LSD]]. Moreover, plant N-alkylamides have a wide range of biological functionalities.<ref>{{Cite journal|doi=10.1016/j.jep.2012.05.038|title=Alkamid database: Chemistry, occurrence and functionality of plant N-alkylamides|year=2012|last1=Boonen|first1=Jente|last2=Bronselaer|first2=Antoon|last3=Nielandt|first3=Joachim|last4=Veryser|first4=Lieselotte|last5=De Tré|first5=Guy|last6=De Spiegeleer|first6=Bart|journal=Journal of Ethnopharmacology|volume=142|issue=3|pages=563–90|pmid=22659196}}</ref>
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| ==Amide synthesis==<!-- This section is linked from [[Organic reaction]] -->
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| Amides are commonly formed via reactions of a [[carboxylic acid]] with an [[amine]]. Many methods are known for driving the unfavorable equilibrium to the right:
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| :RCO<sub>2</sub>H + R'R"NH <math>\overrightarrow{\leftarrow}</math> RC(O)NR'R" + H<sub>2</sub>O
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| For the most part, these reactions involve "activating" the carboxylic acid and the best known method, the [[Schotten-Baumann reaction]], which involves conversion of the acid to the [[acid chloride]]s:
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| :[[Image:SimpleAmideFormationByCondensation.png|400px|Amide bond formation]]
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| <!--to include: *In [[solid phase peptide synthesis]]-->
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| {| class="wikitable sortable" style="background-color:white;float: center; border-collapse: collapse; margin: 0em 1em;" border="1" cellpadding="2" cellspacing="0"
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| ! width=200px|Reaction name !! Substrate !! class="unsortable" | Details
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| |-
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| |valign=top | [[Beckmann rearrangement]]
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| |valign=top|cyclic ketone
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| | reagent: [[hydroxylamine]] and acid
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| |-
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| |valign=top| [[Schmidt reaction]]
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| |valign=top|ketones
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| | reagent: hydrazoic acid
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| |-
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| |valign=top| nitrile hydrolysis
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| |valign=top|nitrile
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| |reagent: water; acid catalyst
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| |-
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| | [[Willgerodt-Kindler reaction]]
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| | aryl alkyl ketones
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| | sulfur and morpholine
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| |-
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| |[[Passerini reaction]]
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| |carboxylic acid, ketone or aldehyde
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| |-
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| |[[Ugi reaction]]
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| | isocyanide, carboxylic acid, ketone, primary amine
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| |-
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| |'''Bodroux reaction'''<ref>{{Cite journal|author=Bodroux F.|journal=Bull. Soc. Chim. France|year= 1905|volume= 33|pages= 831}}</ref><ref>{{cite web|title=Bodroux reaction |publisher= Institute of Chemistry, Skopje, Macedonia|url=http://www.pmf.ukim.edu.mk/PMF/Chemistry/reactions/bodroux1.htm}}</ref>
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| |[[carboxylic acid]], [[Grignard reagent]] with an [[aniline]] derivative ArNHR'
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| | [[Image:Bodroux reaction.png|400px|Bodroux reaction]]
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| |-
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| |'''Chapman rearrangement'''<ref>{{Cite journal|author=Schulenberg, J. W.; Archer, S. |title=The Chapman Rearrangement|journal=[[Organic Reactions|Org. React.]]|year=1965|volume=14|doi=10.1002/0471264180.or014.01}}</ref><ref>{{Cite journal|doi=10.1039/CT9252701992|title=CCLXIX.—Imino-aryl ethers. Part III. The molecular rearrangement of ''N''-phenylbenziminophenyl ether |year=1925|last1=Chapman|first1=Arthur William|journal=Journal of the Chemical Society, Transactions|volume=127|pages=1992}}</ref>
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| |aryl [[imidate|imino ether]]
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| |for ''N,N''-diaryl amides. The [[reaction mechanism]] is based on a [[nucleophilic aromatic substitution]].<ref>{{Cite book|title=Advanced organic Chemistry, Reactions, mechanisms and structure|edition= 3rd |author=March, Jerry |isbn= 0-471-85472-7}}</ref> [[Image:Chapman Rearrangement.png|Left|300px|Chapman Rearrangement]]
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| |-
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| | '''[[List of organic reactions|Leuckart amide synthesis]]''' <ref>{{Cite journal|author= [[Rudolf Leuckart (chemist)|Leuckart, R. ]] |journal=[[Berichte der deutschen chemischen Gesellschaft]]|doi=10.1002/cber.188501801182|title= Ueber einige Reaktionen der aromatischen Cyanate|year= 1885|volume= 18|pages= 873–877}}</ref>
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| | [[isocyanate]]
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| | Reaction of arene with isocyanate catalysed by [[aluminium trichloride]], formation of aromatic amide.
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| |-
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| |}
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| ===Other methods===
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| The seemingly simple direct reaction between an [[alcohol]] and an [[amine]] to an amide was not tried until 2007 when a special [[ruthenium]]-based [[catalyst]] was reported to be effective in a so-called dehydrogenative acylation:<ref>{{Cite journal|doi=10.1126/science.1145295|title=Direct Synthesis of Amides from Alcohols and Amines with Liberation of H<sub>2</sub>|year=2007|last1=Gunanathan|first1=C.|last2=Ben-David|first2=Y.|last3=Milstein|first3=D.|journal=Science|volume=317|issue=5839|pages=790–2|pmid=17690291}}</ref> | |
| :[[Image:DehydrogenativeAmidation.svg|500px|Synthesis of Amides from Alcohols and Amines with Liberation of H2]]
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| The generation of hydrogen gas compensates for unfavorable thermodynamics. The reaction is believed to proceed by one dehydrogenation of the alcohol to the [[aldehyde]] followed by formation of a [[hemiaminal]] and the after a second dehydrogenation to the amide. Elimination of water in the hemiaminal to the imine is not observed.
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| Amides can also be formed from esters. Esters react slowly with amines to yield amides.<ref>{{cite book|last=Klein|first=David|title=Organic Chemistry|year=2011|publisher=John Wiley & Sons, Inc.|location=The United States of America|isbn=0471756148|pages=1003|url=http://books.google.com/?id=SsX9pbarkQkC&pg=PA1006&dq=organic+chemistry+david+%22970-1029hr.indd%22#v=onepage&q=organic%20chemistry%20david%20%22970-1029hr.indd%22&f=false}}</ref>
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| == Amide reactions ==<!-- This section is linked from [[Organic reaction]] -->
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| Amides undergo many chemical reactions, usually through an attack on the [[carbonyl]] breaking the carbonyl double bond and forming a tetrahedral intermediate. [[Thiols]], [[hydroxyl]]s and [[amines]] are all known to serve as nucleophiles. Owing to their resonance stabilization, amides are less reactive under physiological conditions than [[ester]]s. Enzymes, e.g. [[peptidase]]s or artificial catalysts, are known to accelerate the hydrolysis reactions. They can be hydrolysed in hot [[alkali]], as well as in strong [[acid]]ic conditions. Acidic conditions yield the carboxylic acid and the ammonium ion while basic hydrolysis yield the carboxylate ion and ammonia. Amides are also versatile precursors to many other [[functional group]]s.
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| {| class="wikitable sortable" style="background-color:white;float: center; border-collapse: collapse; margin: 0em 1em;" border="1" cellpadding="2" cellspacing="0"
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| ! width=200px|Reaction name !! Product !! class="unsortable" | Comment
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| |-
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| |valign=top | dehydration
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| |valign=top|nitrile
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| | reagent: phosphorus pentoxide
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| |-
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| |valign=top| [[Hofmann rearrangement]]
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| |valign=top|amine with one fewer carbon atoms
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| |reagents: bromine and sodium hydroxide
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| |-
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| |valign=top| [[amide reduction]]
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| |valign=top| amine
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| |reagent: [[lithium aluminium hydride]]
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| |-
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| |[[Vilsmeier–Haack reaction]]
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| |[[imine]]
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| | POCl<sub>3</sub>, aromatic substrate, formamide
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| |-
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| |}
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| ==See also==
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| * [[Metal amides]]
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| ==References==
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| {{reflist}}
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| ==External links==
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| *[http://www.organic-reaction.com/synthetic-protocols/coupling-reagents-in-amide-synthesis/ Amide synthesis (coupling reaction) – Synthetic protocols] from organic-reaction.com
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| *[http://www.rsc.org/Chemsoc/Chembytes/IUPACGoldbook.asp IUPAC Compendium of Chemical Terminology]
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| {{Functional Groups}}
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| [[Category:Amides| ]]
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| [[Category:Functional groups]]
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These are only a limited of numerous categories folks are put into based on their fat. So how do you know where you fit? There are virtually hundreds of charts to measure by, sow which one functions best?
If most of the population is overweight (according to the bmi chart) the error inside logic might be which the population is right and the bmi chart is incorrect.
What have you just performed bmi chart men mathematically? We've doubled each dimension. In the task of doing which, we've octupled the amount of bricks plus octupled the volume of the bricks. The 8 is 2 raised to the third power.
The body is about 60% water. Normally we should drink 2.4 liters (81.15 ounces) of water each day thus that the body could function correctly according to the U.S. Geology Survey (USGS) Water Resources for the United States. When losing weight you need to drink 64 ounces of water per pound of lean body mass. Which means we will need to double that amount if you're physically active or overweight (as much as 128 oz. if you're 200lbs.) As reported by the Mayo Clinic, The Institute of Medicine advises which men consume roughly 3 liters (regarding 13 cups) of total beverages a day and women consume 2.2 liters (regarding 9 cups) of total beverages a day.
Lets begin with an ordinary brick, like the multi-colored 1 at proper. We like to create a tiny brick pile that has the same proportions as the initially brick, however is twice because big in every 3 dimensions. First you add a brick, in purchase to double the length. Then alongside that, we add two more bricks to double the width.
More direct evidence showing the guy needs is studies where subjects have been rating images of real persons. Men found in bmi chart women this form of research which women with ratio of .70 to .71 were more attractive than ladies with ratio of .73 to .74 (Rempala & Garvey, 2007). Similar finding has been found inside many studies. As an example it was found that not only do guys like a Waits-to-Hip ratio about .7, but they also have a strong, non-linear, preference based on female BMI (Body mass index). The many desirable bodies had Waist-to-Hip ratio around the ideal range of .7, nevertheless the desirability was dependent on BMI (Tovee et al, 1999).
34.Speed at 40/Beating your PR:There have been many articles regarding how ladies are older ladies are getting faster plus staying there (see ABC News article on Yale University Study). As you gain experience, you become better runners. We know to run the tangents, prepare correctly, and read strategies like numerous you have indexed here. We furthermore have more time to train as our kids get older.
Then, how can you go from finding the online BMI chart? A variety of time-tested exercise routines for fat reduction are accessible online. You'll be able to receive began inside real time.