231343
Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:
1 $1>2>3>4$
2 $4>3>2>1$
3 $2>1>3>4$
4 $2>3>1>4$
Explanation:
In benzene, ring have symmetrical distribution of $\pi$-electron. Toluene have $+\mathrm{I}$ effect, Hence the $\pi$-electron is concentrated at ortho and para position and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. In chlorobenzene, six electron of chlorine donate in benzene ring and delocalized and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. but Nitrobenzene have $-\mathrm{I}$ effect and pull the electron from benzene ring, and electrophile attack in -0 position. Hence the order of reactivity $2>3>1>4$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231344
The nucleophilicity order is correctly represented by
Nucleophlicity order depend on the conjugate acid of the nucleophile. This acid is strong when nucleophilicity of nucleophile is wear. Hence, the order of conjugate acid is- $\mathrm{CH}_{4}<\mathrm{NH}_{3}<\mathrm{H}_{2} \mathrm{O}<\mathrm{HF}$ And order of nucleophilicity is- $\mathrm{CH}_{3}^{-}>\mathrm{NH}_{2}^{-}>\mathrm{OH}^{-}>\mathrm{F}^{-}$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231349
A reaction $A \rightarrow B$ follows a second order kinetic. Doubling the concentration of $A$ will increase the rate of formation of $B$ by a factor of :
1 $1 / 4$
2 4
3 $1 / 2$
4 2
Explanation:
Rate of formation of B increases by factor of 4 when concentration of $\mathrm{A}$ is doubled. For second order reaction, $\mathrm{r}=\mathrm{K}[\mathrm{A}]^{2}$ when concentration is doubled, $\mathrm{r}_{1}=\mathrm{K}[2 \mathrm{~A}]^{2}$ $=4 \mathrm{~K}[\mathrm{~A}]^{2}$ Thus, $\mathrm{r}_{1}=4 \mathrm{r}$. ......The new rate becomes 4 times.
BCECE-2005
GENERAL ORGANIC CHEMISTRY
231352
Which of the following statements is not correct?
1 Methylamine is more basic than $\mathrm{NH}_{3}$
2 Amines form hydrogen bonds
3 Ethylamine has higher boiling point than propane
4 Dimethylamine is less basic than methylamine
Explanation:
(i) Due to more $+\mathrm{I}$ effect in methylamine, it is more basic than $\mathrm{NH}_{3}$. (ii) Amines form hydrogen bonds due to high electronegativity difference between $\mathrm{H}$ and $\mathrm{N}$. (iii) Ethyl amine has higher boiling point than propane, due to polarity. (iv) Diethylamine is more basic than methyleamine due to higher $+\mathrm{I}$ effect. Hence, (d) is incorrect statement.
NEET Test Series from KOTA - 10 Papers In MS WORD
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GENERAL ORGANIC CHEMISTRY
231343
Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:
1 $1>2>3>4$
2 $4>3>2>1$
3 $2>1>3>4$
4 $2>3>1>4$
Explanation:
In benzene, ring have symmetrical distribution of $\pi$-electron. Toluene have $+\mathrm{I}$ effect, Hence the $\pi$-electron is concentrated at ortho and para position and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. In chlorobenzene, six electron of chlorine donate in benzene ring and delocalized and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. but Nitrobenzene have $-\mathrm{I}$ effect and pull the electron from benzene ring, and electrophile attack in -0 position. Hence the order of reactivity $2>3>1>4$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231344
The nucleophilicity order is correctly represented by
Nucleophlicity order depend on the conjugate acid of the nucleophile. This acid is strong when nucleophilicity of nucleophile is wear. Hence, the order of conjugate acid is- $\mathrm{CH}_{4}<\mathrm{NH}_{3}<\mathrm{H}_{2} \mathrm{O}<\mathrm{HF}$ And order of nucleophilicity is- $\mathrm{CH}_{3}^{-}>\mathrm{NH}_{2}^{-}>\mathrm{OH}^{-}>\mathrm{F}^{-}$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231349
A reaction $A \rightarrow B$ follows a second order kinetic. Doubling the concentration of $A$ will increase the rate of formation of $B$ by a factor of :
1 $1 / 4$
2 4
3 $1 / 2$
4 2
Explanation:
Rate of formation of B increases by factor of 4 when concentration of $\mathrm{A}$ is doubled. For second order reaction, $\mathrm{r}=\mathrm{K}[\mathrm{A}]^{2}$ when concentration is doubled, $\mathrm{r}_{1}=\mathrm{K}[2 \mathrm{~A}]^{2}$ $=4 \mathrm{~K}[\mathrm{~A}]^{2}$ Thus, $\mathrm{r}_{1}=4 \mathrm{r}$. ......The new rate becomes 4 times.
BCECE-2005
GENERAL ORGANIC CHEMISTRY
231352
Which of the following statements is not correct?
1 Methylamine is more basic than $\mathrm{NH}_{3}$
2 Amines form hydrogen bonds
3 Ethylamine has higher boiling point than propane
4 Dimethylamine is less basic than methylamine
Explanation:
(i) Due to more $+\mathrm{I}$ effect in methylamine, it is more basic than $\mathrm{NH}_{3}$. (ii) Amines form hydrogen bonds due to high electronegativity difference between $\mathrm{H}$ and $\mathrm{N}$. (iii) Ethyl amine has higher boiling point than propane, due to polarity. (iv) Diethylamine is more basic than methyleamine due to higher $+\mathrm{I}$ effect. Hence, (d) is incorrect statement.
231343
Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:
1 $1>2>3>4$
2 $4>3>2>1$
3 $2>1>3>4$
4 $2>3>1>4$
Explanation:
In benzene, ring have symmetrical distribution of $\pi$-electron. Toluene have $+\mathrm{I}$ effect, Hence the $\pi$-electron is concentrated at ortho and para position and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. In chlorobenzene, six electron of chlorine donate in benzene ring and delocalized and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. but Nitrobenzene have $-\mathrm{I}$ effect and pull the electron from benzene ring, and electrophile attack in -0 position. Hence the order of reactivity $2>3>1>4$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231344
The nucleophilicity order is correctly represented by
Nucleophlicity order depend on the conjugate acid of the nucleophile. This acid is strong when nucleophilicity of nucleophile is wear. Hence, the order of conjugate acid is- $\mathrm{CH}_{4}<\mathrm{NH}_{3}<\mathrm{H}_{2} \mathrm{O}<\mathrm{HF}$ And order of nucleophilicity is- $\mathrm{CH}_{3}^{-}>\mathrm{NH}_{2}^{-}>\mathrm{OH}^{-}>\mathrm{F}^{-}$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231349
A reaction $A \rightarrow B$ follows a second order kinetic. Doubling the concentration of $A$ will increase the rate of formation of $B$ by a factor of :
1 $1 / 4$
2 4
3 $1 / 2$
4 2
Explanation:
Rate of formation of B increases by factor of 4 when concentration of $\mathrm{A}$ is doubled. For second order reaction, $\mathrm{r}=\mathrm{K}[\mathrm{A}]^{2}$ when concentration is doubled, $\mathrm{r}_{1}=\mathrm{K}[2 \mathrm{~A}]^{2}$ $=4 \mathrm{~K}[\mathrm{~A}]^{2}$ Thus, $\mathrm{r}_{1}=4 \mathrm{r}$. ......The new rate becomes 4 times.
BCECE-2005
GENERAL ORGANIC CHEMISTRY
231352
Which of the following statements is not correct?
1 Methylamine is more basic than $\mathrm{NH}_{3}$
2 Amines form hydrogen bonds
3 Ethylamine has higher boiling point than propane
4 Dimethylamine is less basic than methylamine
Explanation:
(i) Due to more $+\mathrm{I}$ effect in methylamine, it is more basic than $\mathrm{NH}_{3}$. (ii) Amines form hydrogen bonds due to high electronegativity difference between $\mathrm{H}$ and $\mathrm{N}$. (iii) Ethyl amine has higher boiling point than propane, due to polarity. (iv) Diethylamine is more basic than methyleamine due to higher $+\mathrm{I}$ effect. Hence, (d) is incorrect statement.
231343
Identify the correct order of reactivity in electrophilic substitution reactions of the following compounds:
1 $1>2>3>4$
2 $4>3>2>1$
3 $2>1>3>4$
4 $2>3>1>4$
Explanation:
In benzene, ring have symmetrical distribution of $\pi$-electron. Toluene have $+\mathrm{I}$ effect, Hence the $\pi$-electron is concentrated at ortho and para position and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. In chlorobenzene, six electron of chlorine donate in benzene ring and delocalized and electrophile attack at $-\mathrm{o}$ and $-\mathrm{p}$ position. but Nitrobenzene have $-\mathrm{I}$ effect and pull the electron from benzene ring, and electrophile attack in -0 position. Hence the order of reactivity $2>3>1>4$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231344
The nucleophilicity order is correctly represented by
Nucleophlicity order depend on the conjugate acid of the nucleophile. This acid is strong when nucleophilicity of nucleophile is wear. Hence, the order of conjugate acid is- $\mathrm{CH}_{4}<\mathrm{NH}_{3}<\mathrm{H}_{2} \mathrm{O}<\mathrm{HF}$ And order of nucleophilicity is- $\mathrm{CH}_{3}^{-}>\mathrm{NH}_{2}^{-}>\mathrm{OH}^{-}>\mathrm{F}^{-}$
Assam CEE-2014
GENERAL ORGANIC CHEMISTRY
231349
A reaction $A \rightarrow B$ follows a second order kinetic. Doubling the concentration of $A$ will increase the rate of formation of $B$ by a factor of :
1 $1 / 4$
2 4
3 $1 / 2$
4 2
Explanation:
Rate of formation of B increases by factor of 4 when concentration of $\mathrm{A}$ is doubled. For second order reaction, $\mathrm{r}=\mathrm{K}[\mathrm{A}]^{2}$ when concentration is doubled, $\mathrm{r}_{1}=\mathrm{K}[2 \mathrm{~A}]^{2}$ $=4 \mathrm{~K}[\mathrm{~A}]^{2}$ Thus, $\mathrm{r}_{1}=4 \mathrm{r}$. ......The new rate becomes 4 times.
BCECE-2005
GENERAL ORGANIC CHEMISTRY
231352
Which of the following statements is not correct?
1 Methylamine is more basic than $\mathrm{NH}_{3}$
2 Amines form hydrogen bonds
3 Ethylamine has higher boiling point than propane
4 Dimethylamine is less basic than methylamine
Explanation:
(i) Due to more $+\mathrm{I}$ effect in methylamine, it is more basic than $\mathrm{NH}_{3}$. (ii) Amines form hydrogen bonds due to high electronegativity difference between $\mathrm{H}$ and $\mathrm{N}$. (iii) Ethyl amine has higher boiling point than propane, due to polarity. (iv) Diethylamine is more basic than methyleamine due to higher $+\mathrm{I}$ effect. Hence, (d) is incorrect statement.