The Correct order of pKa value of the follwing compound will be
As we know that acidic b ehaviour
Then the least acidic com pound will have highest pKa. Here, conjugate base of Q will be most stable and thus, will be most acidic and thus Q will be most stable and thus, will be most acidic and thus Q have lowest pKa . On the other hand T will be more acidic as compared to S. because S involves cross conjugation. U will be least acidic. Thus, order of pKa value will be
Q < T < S < P < R < U
The correct order of acidic nature of following compound is
Conjugate base of I, II. Ill, IV and V are
Here. II will be the most stable because of extensive delocalization and equal contributing resonance structure, followed by V in which negative charge is delocalized over additional phenyl ring.
Thus, acidity order will be
II > V > IV > III > I
The acidic behaviour of the following substituted benzoic acid will be in the order of
Electron donating group decreases acidic behaviour.
• For hyper conjugation and resonance to happen, the overlapping atom must be planer
• The moment, there is deviation from planarity, because of any reason (here because of steric repulsion) the said effect will minimize or will be diminished.
Becuase of steric effect least donation will be in I, thus will be most acidic Hence, acidic order will be I > II > III.
The correct order for the rates of electrophilic aromatic substitution of the following compound is
Rate of electrophilic aromatic substitution reaction depends upon availability of electron cloud
• Effect of an atom as an electron withdrawing group will be more, when it will be present in the ring, as compared to when it will present outside the ring. Thus, the rate of EAS will be I > III > II. Hence, option (d) is correct.
Among the bromide l-lll given below, the order of their reactivity in the SN1 reaction
Rate of SN1 reaction ∝ stability of carbocation
Thus, stability order will be III > I > II
Hence, rate of SN1 will also be in same order III > I > II
Choose the incorrect statement about tropolone
it exist predominately in the enol form, in which O-H bond is considerably polar, hence have high dipole moment.
Since, it predominately exist in enol form. It gives reaction corresponding to phenol and not corresponding to ketone. That is why it given FeClj test as well as Reimer Tiemann reaction, but does not gives DNP test.
Among the following molecule. The most acidic molecule is:
The decreasing order ofnucleophilicity for the following anions is
How many compound(s) will not rotate the plane polarized light.
Number of non-aromatic compound is / are ___________
The increasing order of acidity of the following molecules.
The collect order of increasing reactivity towards nucleophilic addition for the following carbonyl derivative.
Reactivity towards nucleophile means electrophilicity. Electrophilic character at Carbonyl carbon depends upon the neighbouring group. Electron releasing group decrease electrophilicity and electron withdrawing group increase electrophilicity. Negative charge containing atom are better donar as compared to lone pair containing atom. Less electronegative atom (N) is better donar as compared to more electronegative atom (O). So electrophilic order
Which one of the following has highest pKb ?
Dipole moment of which ketone is maximum ?
Incorrect order of acidity
More stabilized conjugate base with more acidity
Pickout the incorrect statement
Resonance involve movement of charge in bond whereas tautomerism involved movemerts of atom takes place.
Select the incorrect statements
having lower activation energy so they act as more nucleophile.
x = number of (+M) group attached with phenyl ring, so the value of x is
Lone pair- containing atom with conjugation show (+M) effect.
A, B, E, F ( + M ) effect
C, D, G, H ( - M ) effect
Number of non-aromatic compound given below.
A → Aromatic
B → Aromatic
C → Non-aromatic
D → Aromatic
E → Aromatic
D → Aromatic