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ethene doesn't get oxidised to ethanedioic acid right?
ethene (under strong oxidation, from hot kmno4, H+) -> methanal -> methanoic acid -> H2CO3 -> CO2 + H2O
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ethanedioic acid can only be generated/oxidised from a few compounds
e.g. butan-1,3-diene, and
ethene -> ethane-1,2-diol -> ethanedioic acid
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methanal and methanoic acid only generated during intermediate steps from the oxidation of terminal alkene,
no methanal and methanoic acid is generated from oxidation of ethene?
ethene (mild oxidation)-> ethane-1,2-diol -> ethanedioic acid -> H2CO3 -> CO2 + H2O
why is cold conc kmno4 mild oxidation despite kmno4 very strong O.A.? becos factor of temperature? temperature such strong influencing factor
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All right stop. Your (annoyingly multiple) questions show that you still don't understand the correct process of oxidation. You need to ask your school teacher or private tutor to show you face-to-face in-person, exactly how oxidation occurs step-by-step from any particular reactant.
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made easy org chem book page 104
btm of page
Cl2(l) to be used as an inert reagent for the electrophilic substitution of Cl or RCO to benzene? Cl2 exist as gas in room temp, so how is Cl2 used? is it necessary to carry out rxn at temp where Cl2 exist as liquid?
ok i figured out alr.
Cl2 need not be in liquid state. its alright to use Cl2(g). just carry out reaction in anhydrous conditions.
Cl2 is needed in the mechanism.
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page 102 organic made easy
top of page
what does he mean by conjugated ring exhibits a stabilisation stronger than conjugation alone?
does he meant that/ he is comparing conjugation between 2 double bond , or 1 double-single-double bond, compared to rings with multiple alternating single and double bonds?
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pg 110 org made easy writes temperature is needed for Esub of halogen into benzene and methylbenzene.
chankimseng's is room temp for all
http://www.chemguide.co.uk/organicprops/arenes/halogenation.html
also writes r.t.
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pg 112 , same book as above
lone pair of O resides in a sp3 hybridised orbital, can undergo delocalisation? i thought it's only for lone pairs residing in unhybridised p orbitals
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Originally posted by Flying grenade:
page 102 organic made easy
top of page
what does he mean by conjugated ring exhibits a stabilisation stronger than conjugation alone?
does he meant that/ he is comparing conjugation between 2 double bond , or 1 double-single-double bond, compared to rings with multiple alternating single and double bonds?
He means that as compared to conjugation in straight chain, complete conjugation throughout a ring (with same no. of double bonds in the resonance contributors) confers greater stability (this is known as aromaticity). Why? Count the no. of partial double bonds in the resonance hybrid for straight chain vs ring. -
omg thx ultima.
thanks god ultima for your kind reply and explanation.
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Originally posted by Flying grenade:
pg 110 org made easy writes temperature is needed for Esub of halogen into benzene and methylbenzene.
chankimseng's is room temp for all
http://www.chemguide.co.uk/organicprops/arenes/halogenation.html
also writes r.t.
You've already done your own research into 3 sources, and can come to your own conclusion. My help is not needed here. Learn to be independent. Little things you can make your own decision, no need to ask me.(Fyi, in this particular case, as long as you did include the Lewis acid catalyst, Cambridge will accept either version, as using a little bit of heat to increase the rate of reaction does not result in disastrous side reactions and hence will not negate the mark, unlike say, if you included UV light.)
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Originally posted by Flying grenade:
pg 112 , same book as above
lone pair of O resides in a sp3 hybridised orbital, can undergo delocalisation? i thought it's only for lone pairs residing in unhybridised p orbitals
That's exactly right. Since the lone pair on the O atom in phenol *is* indeed delocalized by resonance into the benzene ring, obviously the lone pair doesn't occupy an sp3 hybridized orbital, geddit? -
err, straight chain alkenes have 5 partial double bonds, whereas ring have 6?
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Originally posted by Flying grenade:
err, straight chain alkenes have 5 partial double bonds, whereas ring have 6?
That's why. -
Originally posted by UltimaOnline:
That's exactly right. Since the lone pair on the O atom in phenol *is* indeed delocalized by resonance into the benzene ring, obviously the lone pair doesn't occupy an sp3 hybridized orbital, geddit?i dun, george chong writes "lp in sp3 hybridised orbital of O is co-planar with the p orbitals of the ring, and is able to delocalise into b.ring"
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Originally posted by Flying grenade:
i dun, george chong writes "lp in sp3 hybridised orbital of O is co-planar with the p orbitals of the ring, and is able to delocalise into b.ring"
I've already given you all the clues you need. Anything further, go ask your school teacher or private tutor. -
obviously the lone pair resides in unhybridised p orbital. George chong wrote this wrongly (page 112)
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https://www.quora.com/Organic-Chemistry-SP-hybridization-or-SP3-hybridization-in-Oxygen
did the person who answered wrote wrongly? he wrote O is sp2
O shld be sp3 hybridised when 2 bonds are formed and having 2 remaining lone pairs
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https://sg.answers.yahoo.com/question/index?qid=20120531055003AAjqf14
How does sp3 hybridization in oxygen take place? (in water)?
Only one 2s2 electron is promoted. That would make 4 orbitals which do not have the same energy. These are then hybridized and now create sp3. These sp3 have four bonding sites. Two of the 4 are taken up with Hydrogen. Using VSEPR theory this creates a bond angle of 104.5 degrees.
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Go ask your school teacher or private tutor lah.
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http://www.chemguide.co.uk/basicorg/bonding/carbonyl.html
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pg 136
什么(semo) precpitate is formed? AgX? what is added to the compounds? he didn't mention
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http://www.chemguide.co.uk/organicprops/haloalkanes/agno3.html
for hydrolysis of haloalkanes