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The sigma bond energy of C-H bond in C2H6 is:
(a)
Sigma bond is the first bond formed between any two atoms. ... The C−H bond energy in C2H6 is 99 kcal or 413 KJ/mol
Which of the following is strongest nucleophile?
(d) The order of nucleophilicity depends upon the nature of alkyl group ‘ R' on which a nucleophile to attack as well as on nature of solvent. However, if these are same, then weaker is acid, stronger is base, i.e., stronger is nucleophilicity. This acidic character is:
HI > HBr > HCI > HCN > H2O > EtOH
In hyperconjugation, the atom involved is:
In hyperconjugation, the stabilization of a molecule or ion is achieved by the delocalization of electrons from an adjacent C-H σ bond into an empty or partially filled p-orbital. Therefore, the α-H atom is involved in hyperconjugation.
The stability of 2,3-dimethyl but-2-ene is more than 2-butene. This can be explained in terms of:
The former possesses 12α-H atom whereas, later possesses six α-H atom. More is the no. α-H atom, more is delocalisation and more is stability.
Who pointed out the concept of hyperconjugation?
(a)
Those chemists who received their training in physical organic chemistry in the pre-1975 era probably remember the Baker-Nathan effect. The paper will then examine how Baker and his collabora- tor Nathan discovered what was believed to be the first example of hyperconjugation.
(CH3)4N+ is neither an electrophile, nor a nucleophile because it:
Note the fact.
Which of the following is an electrophilic reagent?
(b)
BF3 is a electron deficient compound . it has 6 electron in place of 8 electron around
The +I.E.(inductive effect) is shown by:
(a) -CH3 is electron repelling group
The-I effect is shown by:
(a) -COOH is electron withdrawing group.
Which of the following is singlet carbene ?
(b) An organic reaction intermediate, neutral species having divalent carbon atom with six valence electron out of which two are present in same orbital with opposite spin is called singlet carbene.
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