231466
Which of the following species is a nucleophile?
1 $\stackrel{+}{\mathrm{N}} \mathrm{O}_{2}$
2 $: \mathrm{CX}_{2}$
3 $: \ddot{\mathrm{N}}_{2}^{-}$
4 $\cdot \mathrm{CH}_{3}$
Explanation:
Nucleophiles are electron donating species. Among the given, only : $\ddot{\mathrm{NH}}_{2}^{-}$has a tendency to give lone pair of electrons, so it is a nucleophile.
JCECE - 2011
GENERAL ORGANIC CHEMISTRY
231472
The correct order of basic strength of the following are
1
2
3
4
Explanation:
$+\mathrm{I}$ effect increase the basicity and delocalization decrease the basicity. The carbonyl group delocalized the lone pair electron of N. Hence, it's decrease the basicity but in option ' $d$ ' group is attached at $-\mathrm{M}$-position which is not delocalized the lone pair electron of $\mathrm{N}$ (only delocalized by phenyl group which is same for all) The order of basicity isIV $>$ III $>$ II $>$ I
JIPMER-2017
GENERAL ORGANIC CHEMISTRY
231480
Hyper conjugation is most useful for stabilizing which of the following carboctions?
1 Neo-pentyl
2 Tert-butyl
3 Iso-propy
4 Ethyl
Explanation:
We know that in electrophilic aromatic substitution, the nitrogroup is an electron withdrawing group which decreases electron density at metaposition. Therefore $\mathrm{NO}_{2}$ group is meta directing.
JIPMER-2011
GENERAL ORGANIC CHEMISTRY
231481
Which of the following statements is correct?
1 + I effect stabilizes a carbanion
2 + I effect stabilizes a carbocation
3 - I effect stabilizes a carbanion
4 - I effect stabilizes a carbocation
Explanation:
Positive inductive effect (+I effect) is arises due to electron releasing group $(\mathrm{y})$. $+\mathrm{I}$ group stabilizes carbocation due to dispersion of positive charge on the + I effect group also.
NEET Test Series from KOTA - 10 Papers In MS WORD
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GENERAL ORGANIC CHEMISTRY
231466
Which of the following species is a nucleophile?
1 $\stackrel{+}{\mathrm{N}} \mathrm{O}_{2}$
2 $: \mathrm{CX}_{2}$
3 $: \ddot{\mathrm{N}}_{2}^{-}$
4 $\cdot \mathrm{CH}_{3}$
Explanation:
Nucleophiles are electron donating species. Among the given, only : $\ddot{\mathrm{NH}}_{2}^{-}$has a tendency to give lone pair of electrons, so it is a nucleophile.
JCECE - 2011
GENERAL ORGANIC CHEMISTRY
231472
The correct order of basic strength of the following are
1
2
3
4
Explanation:
$+\mathrm{I}$ effect increase the basicity and delocalization decrease the basicity. The carbonyl group delocalized the lone pair electron of N. Hence, it's decrease the basicity but in option ' $d$ ' group is attached at $-\mathrm{M}$-position which is not delocalized the lone pair electron of $\mathrm{N}$ (only delocalized by phenyl group which is same for all) The order of basicity isIV $>$ III $>$ II $>$ I
JIPMER-2017
GENERAL ORGANIC CHEMISTRY
231480
Hyper conjugation is most useful for stabilizing which of the following carboctions?
1 Neo-pentyl
2 Tert-butyl
3 Iso-propy
4 Ethyl
Explanation:
We know that in electrophilic aromatic substitution, the nitrogroup is an electron withdrawing group which decreases electron density at metaposition. Therefore $\mathrm{NO}_{2}$ group is meta directing.
JIPMER-2011
GENERAL ORGANIC CHEMISTRY
231481
Which of the following statements is correct?
1 + I effect stabilizes a carbanion
2 + I effect stabilizes a carbocation
3 - I effect stabilizes a carbanion
4 - I effect stabilizes a carbocation
Explanation:
Positive inductive effect (+I effect) is arises due to electron releasing group $(\mathrm{y})$. $+\mathrm{I}$ group stabilizes carbocation due to dispersion of positive charge on the + I effect group also.
231466
Which of the following species is a nucleophile?
1 $\stackrel{+}{\mathrm{N}} \mathrm{O}_{2}$
2 $: \mathrm{CX}_{2}$
3 $: \ddot{\mathrm{N}}_{2}^{-}$
4 $\cdot \mathrm{CH}_{3}$
Explanation:
Nucleophiles are electron donating species. Among the given, only : $\ddot{\mathrm{NH}}_{2}^{-}$has a tendency to give lone pair of electrons, so it is a nucleophile.
JCECE - 2011
GENERAL ORGANIC CHEMISTRY
231472
The correct order of basic strength of the following are
1
2
3
4
Explanation:
$+\mathrm{I}$ effect increase the basicity and delocalization decrease the basicity. The carbonyl group delocalized the lone pair electron of N. Hence, it's decrease the basicity but in option ' $d$ ' group is attached at $-\mathrm{M}$-position which is not delocalized the lone pair electron of $\mathrm{N}$ (only delocalized by phenyl group which is same for all) The order of basicity isIV $>$ III $>$ II $>$ I
JIPMER-2017
GENERAL ORGANIC CHEMISTRY
231480
Hyper conjugation is most useful for stabilizing which of the following carboctions?
1 Neo-pentyl
2 Tert-butyl
3 Iso-propy
4 Ethyl
Explanation:
We know that in electrophilic aromatic substitution, the nitrogroup is an electron withdrawing group which decreases electron density at metaposition. Therefore $\mathrm{NO}_{2}$ group is meta directing.
JIPMER-2011
GENERAL ORGANIC CHEMISTRY
231481
Which of the following statements is correct?
1 + I effect stabilizes a carbanion
2 + I effect stabilizes a carbocation
3 - I effect stabilizes a carbanion
4 - I effect stabilizes a carbocation
Explanation:
Positive inductive effect (+I effect) is arises due to electron releasing group $(\mathrm{y})$. $+\mathrm{I}$ group stabilizes carbocation due to dispersion of positive charge on the + I effect group also.
231466
Which of the following species is a nucleophile?
1 $\stackrel{+}{\mathrm{N}} \mathrm{O}_{2}$
2 $: \mathrm{CX}_{2}$
3 $: \ddot{\mathrm{N}}_{2}^{-}$
4 $\cdot \mathrm{CH}_{3}$
Explanation:
Nucleophiles are electron donating species. Among the given, only : $\ddot{\mathrm{NH}}_{2}^{-}$has a tendency to give lone pair of electrons, so it is a nucleophile.
JCECE - 2011
GENERAL ORGANIC CHEMISTRY
231472
The correct order of basic strength of the following are
1
2
3
4
Explanation:
$+\mathrm{I}$ effect increase the basicity and delocalization decrease the basicity. The carbonyl group delocalized the lone pair electron of N. Hence, it's decrease the basicity but in option ' $d$ ' group is attached at $-\mathrm{M}$-position which is not delocalized the lone pair electron of $\mathrm{N}$ (only delocalized by phenyl group which is same for all) The order of basicity isIV $>$ III $>$ II $>$ I
JIPMER-2017
GENERAL ORGANIC CHEMISTRY
231480
Hyper conjugation is most useful for stabilizing which of the following carboctions?
1 Neo-pentyl
2 Tert-butyl
3 Iso-propy
4 Ethyl
Explanation:
We know that in electrophilic aromatic substitution, the nitrogroup is an electron withdrawing group which decreases electron density at metaposition. Therefore $\mathrm{NO}_{2}$ group is meta directing.
JIPMER-2011
GENERAL ORGANIC CHEMISTRY
231481
Which of the following statements is correct?
1 + I effect stabilizes a carbanion
2 + I effect stabilizes a carbocation
3 - I effect stabilizes a carbanion
4 - I effect stabilizes a carbocation
Explanation:
Positive inductive effect (+I effect) is arises due to electron releasing group $(\mathrm{y})$. $+\mathrm{I}$ group stabilizes carbocation due to dispersion of positive charge on the + I effect group also.
group is attached at $-\mathrm{M}$-position which is not delocalized the lone pair electron of $\mathrm{N}$ (only delocalized by phenyl group which is same for all) The order of basicity isIV $>$ III $>$ II $>$ I