In pyrrole
the electron density is maximum on:
1. 2 and 3
2. 3 and 4
3. 2 and 4
4. 2 and 5
Which among the given molecules can exhibit tautomerism?
1. III only
2. Both I and III
3. Both I and II
4. Both II and III
The correct order with respect to –I effect of the substituents is:
(R = alkyl)
1. –NH2 > –OR < –F
2. –NR2 < –OR < –F
3. –NH2 > –OR > –F
4. –NR2 > –OR > –F
The most stable carbocation among the following is:
1. | 2. | ||
3. | 4. |
The correct statement regarding electrophile is :
1. | Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from another electrophile |
2. | Electrophiles are generally neutral species and can form a bond by accepting a pair of electrons from a nucleophile |
3. | Electrophiles can be either neutral or positively charged species and can form a bond accepting a pair of electrons from a nucleophile |
4. | Electrophile is a negatively charged species and can form a bond by accepting a pair of electrons from a nucleophile |
The IUPAC name of the compound is:
1. 5-formylhex-2-en-3-one
2. 5-methyl-4-2-en-5-el
3. 3-keto-2-methylhex-5-enal
4. 3-keto-2-methylhex-4-enal
The most suitable method used for the separation of 1:1 mixture of ortho and para-nitrophenols is:
1. | Chromatography | 2. | Crystallization |
3. | Steam distillation | 4. | Sublimation |
The correct statement regarding the comparison of staggered and eclipsed conformations of ethane is:
1. | The eclipsed conformation of ethane is more stable than staggered conformation because eclipsed conformation has no torsional strain |
2. | The eclipsed conformation of ethane is more stable than staggered conformation even though the eclipsed conformation has a torsional strain |
3. | The staggered conformation of ethane is more stable than the eclipsed conformation because staggered conformation has no torsional strain |
4. | The staggered conformation of ethane is less stable than eclipsed conformation because staggered conformation has torsional strain |
The correct order of strengths of the carboxylic acids :-
(a) I>II>III
(b) II>III>I
(c) III>II>I
(d) lI>I>IlI
Which among the given molecules can exhibit tautomerisrn?
1. III Only
2. Both I and III
3. Both Iand II
4. Both II and III