Acidic Nature vs Percentage S Characters

Q. Arrange the following compounds in decreasing order of reactivity for hydrolysis reaction.
I. $PhC{H}_{2}Br$
II. $Ph-\stackrel{\stackrel{Br}{|}}{C}H-C{H}_{2}C{H}_3$
III.
IV.

1. I > II > III > IV
2. IV > II > I > III
3. III > IV > II > I
4. IV > III > II > I

Q. The increasing order of reactivity of the following halides for the $S_{N}1$ reaction is
$\left(I\right).C{H}_{3}CH\left(Cl\right)C{H}_{2}C{H}_3$
$\left(II\right).C{H}_{3}C{H}_{2}C{H}_{2}Cl$
$\left(III\right).p-H_{3}CO-C_6{H}_4-C{H}_{2}Cl$

1. $\left(III\right)<\left(II\right)<\left(I\right)$
2. $\left(II\right)<\left(I\right)<\left(III\right)$
3. $\left(I\right)<\left(III\right)<\left(II\right)$
4. $\left(II\right)<\left(III\right)<\left(I\right)$

Q. Acetylenic hydrogens are acidic because

1. sigma electron density of C - H bond in acetylene is nearer to carbon, which has 50% s-character
2. acetylene has only open hydrogen in each carbon
3. acetylene contains least number of hydrogens among the possible hydrocarbons having two carbons
4. Acetylene belongs to the class of alkynes with molecular formula, $C_n{H}_{2n-2}.$

Q. Which of the following alkynes is most acidic?

1. $C{H}_{3}C\equiv CH$
2. $C{H}_{3}C\equiv CC{H}_3$
3. $CH\equiv CH$
4. $C{H}_{3}C{H}_{2}C\equiv CH$

Q. Which of the following alkyl halide is more reactive towards $E1$ reaction?

1. 
2. 
3. 
4. $C{H}_3-Cl$

Q.

Which of the following does not give ${\mathrm{H}}^{+}$ions in aqueous solution?

1. ${\mathrm{H}}_2{\mathrm{CO}}_3$

2. ${\mathrm{C}}_2{\mathrm{H}}_5\mathrm{OH}$

3. ${\mathrm{CH}}_3\mathrm{COOH}$

4. ${\mathrm{H}}_3{\mathrm{PO}}_4$

Q.
Among these compounds, the correct order of resonance energy is

1. I > II > III
2. III > II > I
3. II > III > I
4. II > I > III

Q. The most acidic hydrogen is present in :

1. Ethyne
2. Ethene
3. Benzene
4. Ethane

Q.

Why in ethene angle between carbon hydrogen bonds is slightly less than angle between carbon hydrogen and carbon carbon Bond?

Q. The number of acidic hydrogen atoms in 1-butyne and 2-butyne is respectively.

1. 1, 1
2. 1, 2
3. 1, 0
4. 0, 1

Q. Choose the correct order of acidic strength:
1. Propane
2. Prop-1-ene
3. Prop-1-yne

1. Propane > Prop-1-ene > Prop-1-yne
2. Prop-1-yne > Prop-1-ene > Propane
3. Prop-1-ene> Propane > Prop-1-yne
4. Propane = Prop-1-ene = Prop-1-yne

Q.

The major product $\left[\mathrm{Y}\right]$ in the following reactions is

1. 

2. 

3. 

4. 

Q. Which of the following reaction will not be favourable in the forward direction?

1. $C{H}_{3}ONa+C{H}_{3}COOH\to C{H}_{3}OH+C{H}_{3}COONa$
2. $PhONa+N{H}_3\to PhOH+NaN{H}_2$
3. $HC\equiv CH+NaN{H}_2\to HC\equiv CNa+N{H}_3$
4. $HCOOH+PhONa\to HCOONa+PhOH$

Q.

Whether the conjugate base of ${\mathrm{NH}}_3$ is ${{\mathrm{NH}}_3}^{+}$ or not. Explain why?

Q. Which of the following alkynes is least acidic?

1. $C{H}_{3}C\equiv CC{H}_3$
2. $C{H}_{3}C\equiv CH$
3. $C{H}_{3}C{H}_{2}C\equiv CH$
4. $CH\equiv CH$

Q. Identify the product(s) obtained when hot hydrogen iodide react with benzyl ethyl ether at high temperature?

1. Ethanol
2. Benzyl iodide
3. Ethyl iodide
4. Phenol

Q.

Which of the following Carboxylic acid donot undergo decarboxylation on heating?

1. 

2. 

3. 

4. 

Q. Which of the following acidity order is correct?

1. 1-Alkyne > Alkene > Alkane
2. Alkene > Alkane > 1-Alkyne
3. Alkane > Alkene > 1-Alkyne
4. None of these

Q. Arrange the following in decreasing order of basic strength :

1. $B>C>A$
2. ​​​​​​$C>B>A$
3. $A>C>B$
4. $A>B>C$

Q. Which of the follwing acidity order is correct?

1. 1-Alkyne > Alkene > Alkane
2. None of these
3. Alkene > Alkane > 1-Alkyne
4. Alkane > Alkene > 1-Alkyne

Q. $\beta -$ Elimination or anti-elimination reaction is carried out with base $\left(B^{\ominus }\right)$ as shown.
The following bases are used,
$\left(I\right)\stackrel{\ominus }{O}H\left(II\right)R{O}^{\ominus }\left(III\right)RCO{O}^{\ominus }\left(IV\right)\stackrel{\ominus }{C}N\left(V\right)N{O}_3^{\ominus }$

The decreasing order of reactivity for the above elimination is :

1. $\left(II\right)>\left(I\right)>\left(IV\right)>\left(III\right)>\left(V\right)$
2. $\left(V\right)>\left(III\right)>\left(IV\right)>\left(I\right)>\left(II\right)$
3. $\left(II\right)>\left(I\right)>\left(III\right)>\left(IV\right)>\left(V\right)$
4. $\left(I\right)>\left(II\right)>\left(III\right)>\left(IV\right)>\left(V\right)$

Q. Assertion :Due to ortho effect basic nature of aniline decreases. Reason: It is due to steric hindrance because of solvation of cation.

1. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
2. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
3. Assertion is correct but Reason is incorrect
4. Both Assertion and Reason are incorrect

Q. Which reagent can be used to distinguish between 1-butyne and 2-butyne?

1. alc.$KOH$
2. $alc.KMn{O}_4$
3. $B{r}_2$ water
4. $A{g}^{+}$

Q. Consider the following Carbocations :
I) $C_6{H}_5\leftarrow C{H}_2$
II) $C_6{H}_5\leftarrow C{H}_{2}C{H}_2$
III) $C_6{H}_5\leftarrow CH\leftarrow C{H}_3$
IV) $C_6{H}_5\leftarrow C(C{H}_3{)}_2$

1. I>II>III>IV
2. II>I>III>IV
3. IV>III>II>I
4. IV>III>I>II

Q. Which of the following alkyl halide is more reactive towards $E1$ reaction?

1. 
2. 
3. 
4. $C{H}_3-Cl$

Q. Rank the above compounds with rescept to increasing acidity:

1. 4 < 3 < 1 < 2
2. 2 < 1 < 4 < 3
3. 2 < 1 < 3 < 4
4. 3 < 1 < 2 < 4

Q. Which of the following molecules does not posses a permanent electric dipole moment ?

1. $H_{2}S$
2. $S{O}_2$
3. $S{O}_3$
4. $C{S}_2$

Q. What happens to the bond length of CO Bond in an alcohol(R-OH) and an ether(ROR) as the size of R(alkyl) group increases?

Q. Arrange the following free radicals in order of decreasing stability :

1. $II>I>IV>III$
2. $III>II>I>IV$
3. $I>II>III>IV$
4. $IV>III>I>II$.

Q. Which one is the correct order of acidity ?

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1. $CH\equiv CH>C{H}_2=C{H}_2>C{H}_3-C\equiv CH>C{H}_3-C{H}_3$
2. $CH\equiv CH>C{H}_3-C\equiv CH>C{H}_2=C{H}_2>C{H}_3-C{H}_3$
3. $C{H}_3-C{H}_3>C{H}_2=C{H}_2>C{H}_3-C=CH>CH\equiv CH$
4. $C{H}_2=C{H}_2>C{H}_3-CH=C{H}_2>C{H}_3-C\equiv CH>CH\equiv CH$