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A cyclic molecule or ion having different resonating structure follows Hückel's rule when the number of its π-electrons equals 4n+2 where n is zero or any positive integer.
Example
(4 x (0)) + 2 = 2 π electrons
(4 x (1)) + 2 = 6 π electrons
(4 x (2)) + 2 = 10 π electrons
etc
Taking benzene as an example, it has 3 double bonds so 6 π electrons (2 electrons for each double bond) thus it fits Huckels rule and therefore is aromatic. If the molecule is an ion and has a negative charge, the negative charge is also counted as 2 π electrons. Positive charges on a cyclic molecule are ignored.
Wiki User
∙ 14y ago
Wiki User
∙ 9y agoThe Huckels rule of aromaticity states that a compound is particularly stable if all of its bonding molecular orbitals are filled with paired electrons.
Wiki User
∙ 8y agoHuckel's rule dictates the chemical stability of a planar, aromatic ring with resonance, as in a benzene (C6H6) molecule.
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Why pyrol is aromatic?
because it obeys huckle rule of aromaticity.
Is benzoquinone aromatic?
No - although it has sufficient electrons to obey the Huckel rule (4n+2) pi electrons. The two olefins in the ring are cross-conjugated through the carbonyl groups. The lack of proper conjugation precludes aromaticity. The non aromaticity is evidenced by different bond-lengths around the ring
Aromaticity in non benzenoid compounds?
GIUNNNSLLJTJOHNSON
Why tropylium ion is more stable than triphenyl carbocation?
as because in case of tropylium cation extra stability arises from the attainment of aromaticity as well as extensive conjugation.It contains 6π electrons which is according to Huckel's rule indicate towards the aromatic compound as well as the system is also a resonance stabilized because of delocalisation
What is a simple test to distinguish between an aliphatic compound and an aromatic compound?
Huckels rule. 4n + 2 whereby n is any integer for example 1,2,3 etc. Aromatic compounds will obey huckels rule:- (4 x (1)) + 2 = 6 (4 x (2)) + 2 = 10 (4 x (3)) + 2 = 14 Taking benzene as an example...is it aromatic? Is a six membered ring with 3 double bonds, so 6pi electrons thus obeys huckels rule and is aromatic. Negative charges also count as 2pi electrons and positive charges on a molecule are ignored entirely.
How is huckel rule applied in determining aromaticity?
Huckel's rule is used in aromaticity by stating that monocyclic systems are aromatic. This will happen if there are delocalized electrons.
Why pyrol is aromatic?
because it obeys huckle rule of aromaticity.
Illustrate the difference between aromaticity and antiaromaticity with appropriate examples?
Illustrate the difference between aromaticity and antiaromaticity with appropriate examples?
Is benzoquinone aromatic?
No - although it has sufficient electrons to obey the Huckel rule (4n+2) pi electrons. The two olefins in the ring are cross-conjugated through the carbonyl groups. The lack of proper conjugation precludes aromaticity. The non aromaticity is evidenced by different bond-lengths around the ring
Aromaticity in non benzenoid compounds?
GIUNNNSLLJTJOHNSON
What an aromatic compound?
An aromatic compound is a compound in organic chemistry which exhibits aromaticity.
How many ring structures do pyrimidines have?
Pyrimidine is one ring structure with 4 carbons and 2 nitrogens, linked together in a ring, with a carbon located between the nitrogens. It follows Hucke's rule for aromaticity, and therefore is a NN-heterocyclic aromatic hydrocarbon.
A scientific is a rule used to describe a pattern seen in nature not an explanation of why that pattern might occur.?
Yes
Is a scientific law a rule used to describe a pattern seen in nature not an explanation of why that pattern might occur?
Yes
What Is the rule of thumb stating that if there are two explanations for a phenomenon that the simplest explanation is more often the best one?
k
what Is the rule of thumb stating that if there are two explanations for a phenomenon the simplest explanation is more often the best one?
Positive correlation
Why tropylium ion is more stable than triphenyl carbocation?
as because in case of tropylium cation extra stability arises from the attainment of aromaticity as well as extensive conjugation.It contains 6π electrons which is according to Huckel's rule indicate towards the aromatic compound as well as the system is also a resonance stabilized because of delocalisation
