Why is the gamma-hydrogen in an alpha,beta-unsaturated carbonyl compound also acidic?
142302
Resonance in the pi-electron orbitals.
789425
I think it has to do with the fact that there is a benzene ring on it. The pKa of benzene is around 7 or 8, I believe. So benzene could have a n affect on the level of its acidity. \n\nIt could possibly be harder for a base to pick up a proton off the alcohol on the phenol than on the alcohol on a regular carbon chain, or ring with no double bonds. \n\nbut I'm just guessing.
408703
By Carboxylic acid, let's assume you mean an aliphatic carboylic acid with no electron withdrawing groups attached.\n\nSo let's compare ... acetic acid to phenol.\n\nAcetic acid's pka is 4.76\n\nphenol's pka is 9.95\n\nClearly acetic acid is more acidic. The answers above are essentially correct. A carboxylic acid is stabilized through resonance through the 2 carbonyl groups. The phenoxide anion is stabilized through delocalization of the electrons in a pi system. At the end of the day, though, phenol is still an alcohol and its proton is not given willingly in solution.
445370
well this question was asked two days before.\nsearch for this question u'll get all the knowledge\nstrongest oxo-acid-- HClO4\nstrongest protonic acid--H2SO4\nstrongest lewis acid----SBF5\n btw HF is not consider very strong bcoz F is very small atom and it does not loose H+ very easily.\n\nEDIT: Question(very odd name) there has been acids with negative pH and 0 pH( 0pH is more stronger than 1)
549677
This is a chemistry question, the anomaly is due to Hydrogen bonding.
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Acidic.  Citric acid.
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HBr is a strong acid because of Bromine's electronegativity.
211164
a proton is positively charged and acts as nucleus in a hydrogen atom. let me first explain what is protonation.\nprotonation[prO´tunA´´shun] Pronunciation Key, in chemistry, addition of a proton to an atom, molecule, or ion. The proton is the nucleus of the hydrogen atom; the positive hydrogen ion, H+, consists of a single proton. An example of protonation is the formation of the ammonium group NH4+ from ammonia, NH3. Protonation often occurs in the reaction of an acid with a base to form a salt (see acids and bases; salts). Protonation differs from hydrogenation in that during protonation a change in charge of the protonated species occurs, whereas the charge is unaffected during hydrogenation.\n\n The atom consists of a central, positively charged core, the nucleus, and negatively charged particles called electrons that are found in orbits around the nucleus.\n\nThe Nucleus\n\nAlmost the entire mass of the atom is concentrated in the nucleus, which occupies only a tiny fraction of the atom's volume. The nucleus of an atom consists of neutrons and protons, the neutron being an uncharged particlarticlelinks" href="/encyclopedia/P/proton.html">proton a positively charged one. Their masses are almost equal. Atoms containing the same number of protons but different numbers of neutrons represent different forms, or isotopes, of the same element.\n\nfor more information i will tell u more about electrons.\nSurrounding the nucleus of an atom are its electrons; for a neutral atom, the number of electrons is equal to the atomic number. The outermost electrons of an atom determine its chemical and electrical properties. An atom may combine chemically with another atom in various ways, eieceiving electrons, thus setting up an electrical attraction between the atoms (see ion), or by sharing one or more pairs of electrons (see chemical bond). Because metals have few outermost electrons and tend to give them up easily, they are good conductors of electricity or heat (see conduction).\n\nThe electrons are often described as revolving about the nucleus as the planets revolve about the sun. This picture, however, is misleading. The quantum theory has shown that all particles in motion also have certain wave properties. For a particle the size of an electron, these properties are of considerable importance. As a result the electrons in an atom cannot be pictured as localized in space, but rather should be viewed as smeared out over the entire orbit so that they form a cloud of charge. The electron clouds around the nucleus represent regions in which the electrons are most likely to be found. The shapes of these clouds can be very complex, in marked contrast to the simple elliptical orbits of planets. Surprisingly, the sizes of all atoms are comparable, in spite of the large differences in the number of electrons they contain.\n\ni hope u find my information sufficient.
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All organic acids have a carboxyl group (-COOH) in them.
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It's pentanal, because it's a terminal carbonyl. It's certainly not pentanol, because otherwise you'd have a carbon missing 2 bonds, or a carbon missing 1 bond and an oxygen missing 1.
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G. Yes\n\nH. HNO3 (Nitric acid)\n\nI. Because they do not have carbon\n\nJ. Ba(NO 3)2 (I am not sure what is it called....barium nitroxide??!!)\n\nIf I get these right, I am a genius.....haven't touched chemistry for 10 years now maybe!! OR my teachers were really cool.................\n\n\nI am sure they are right!
111102
cinnamic acid is reduced to the aldehyde and can be further reduced to the alcohol.\nsodium borohydride is caustic b/c the hydride ion(H-1) reacts with water to produce hydrogen gas and the hydroxide ion.  it acts as a strong base.
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So you acetylate the amine, thereby creating an amide. What happens, I think anway, is that the carbonyl is drastically reducing the initial nucleophilicity of the lone pair of the amine, because it's pulling electron density from the nitrogen.
223089
its just two atoms- one hydrogen and one florine, so you have already written the molecular formula.  HF is closely related to HCl (hydrochloric acid) because Cl and F are closely related elements.  But, HCl is a much stronger acid, because it releases from H more easily than F, and HF is special in that its the only acid that can etch glass.
1024314
well, not an analytical fan myself, but here is what I know\n\n1) one strong and board absorption bend at 3650-3200 cm^-1 indicates -OH functional group\n\n2) No peaks just above 3000 cm^-1, no sp2 carbon\n\n3) peaks just right of 3000 cm^-1 indicates saturated carbon chain\n\n4) one peak, sharp, right of 1400 cm^-1 indicates methyl group.
520226
And many nail polishes use acetone as a solvent.  Acetone (aka dimethyl ketone, essentially a propane (3 carbon chain) with a double bonded oxygen on the middle carbon instead of two hydrogens), has some similar properties to formic acid (one carbon with a double bonded oxygen, one hydrogen and an -OH group). Namely that electronegative oxygen hangin' out there (electronegative means it grips electrons in bonds tightly).   That double bonded oxygen tickles some of the same receptors in your schnoz's olfactory cells, regardless of what elese it is attached to. \n\nTry a side by side sniffing of both and see if there is a vague difference.  The formic acid should also have a sour tang on top of the nail polish smell.  That would be that OH group.  When it sits on the same carbon as a double bonded oxygen, that oxygen hogs a lot of the carbon's electrons, making the carbon hog some of the electrons from the OH oxygen, making THAT oxygen hog the hydrogen's electron that much more, freeing up that hydrogen to go all H+ and wander off in the water as an H3O+ sometimes, aka an acid.  All organic acids have that carboxyl group .\n\nWiki has some diagrams of this stuff.\n\nAcetone: http://en.wikipedia.org/wiki/Acetone\nCarboxyl: http://en.wikipedia.org/wiki/Carboxyl\nFormic Acid: http://en.wikipedia.org/wiki/Formic_acid
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Look at their conjugate bases and whichever is more stable will have the weakest acid. PKA values are also easy to prove this becuase it is a realtion of the H+ content.