91Ó°ÊÓ

Which of the following is the correct order of decreasing \(\mathrm{SN}^{2}\) reactivity? \(\quad\) [2007] (a) \(\mathrm{RCH}_{2} \mathrm{X}>\mathrm{R}_{2} \mathrm{CHX}>\mathrm{R}_{3} \mathrm{CX}\) (b) \(\mathrm{R}_{3} \mathrm{CX}>\mathrm{R}_{2} \mathrm{CHX}>\mathrm{RCH}_{2} \mathrm{X}\) (c) \(\mathrm{R}_{2} \mathrm{CHX}>\mathrm{R}_{3} \mathrm{CX}>\mathrm{RCH}_{2} \mathrm{X}\) (d) \(\mathrm{RCH}_{2} \mathrm{X}>\mathrm{R}_{3} \mathrm{CX}>\mathrm{R}_{2} \mathrm{CHX}\)

The correct order of increasing basicity of the given conjugate bases \(\left(\mathrm{R}=\mathrm{CH}_{3}\right)\) is \([2010]\) (a) \(\mathrm{RCO} \overline{\mathrm{O}}<\mathrm{HC} \equiv \overline{\mathrm{C}}<\overline{\mathrm{R}}<\overline{\mathrm{N}} \mathrm{H}_{2}\) (b) \(\overline{\mathrm{R}}<\mathrm{HC} \equiv \overline{\mathrm{C}}<\mathrm{R} \mathrm{CO} \overline{\mathrm{O}}<\overline{\mathrm{N}} \mathrm{H}_{2}\) (c) \(\mathrm{RCO} \overline{\mathrm{O}}<\overline{\mathrm{N}} \mathrm{H}_{2}<\mathrm{HC} \equiv \overline{\mathrm{C}}<\overline{\mathrm{R}}\) (d) \(\mathrm{RCO} \overline{\mathrm{O}}<\mathrm{HC} \equiv \overline{\mathrm{C}}<\overline{\mathrm{N}} \mathrm{H}_{2}<\overline{\mathrm{R}}\)

The strongest acid amongst the following compounds is: (a) \(\mathrm{HCOOH}\) (b) \(\mathrm{CH}_{3} \mathrm{CH}_{2} \mathrm{CH}(\mathrm{Cl}) \mathrm{CO}_{2} \mathrm{H}\) (c) \(\mathrm{ClCH}_{2} \mathrm{CH}_{2} \mathrm{CH}_{2} \mathrm{COOH}\) (d) \(\mathrm{CH}_{3} \mathrm{COOH}\)

A solution of \((-)-1-\) chloro- 1 -phenylethane in toluene racemizes slowly in the presence of a small amount of \(\mathrm{SbCl}_{5}\) due to formation of: [2013] (a) carbocation (b) free radical (c) carbanion (d) carbene

Considering the basic strength of amines in aqueous solution, which one has the smallest \(\mathrm{pK}_{\mathrm{b}}\) value? [2014] (a) \(\left(\mathrm{CH}_{3}\right)_{3} \mathrm{~N}\) (b) \(\mathrm{C}_{6} \mathrm{H}_{3} \mathrm{NH}_{2}\) (c) \(\left(\mathrm{CH}_{3}\right)_{2} \mathrm{NH}\) (d) \(\mathrm{CH}_{3} \mathrm{NH}_{2}\)

The reaction of Propene with \(\mathrm{HOCl}\left(\mathrm{Cl}_{2}+\mathrm{H}_{2} \mathrm{O}\right)\) proceeds through the intermediate (a) \(\mathrm{CH}_{3}-\mathrm{CH}(\mathrm{OH})-\mathrm{CH}_{2}\) (b) \(\mathrm{CH}_{3}-\mathrm{CH}-\mathrm{CH}_{2} \mathrm{Cl}\) (c) \(\mathrm{CH}_{3}-\mathrm{CHCl}-\mathrm{CH}_{2}\) (d) \(\mathrm{CH}_{3}-\mathrm{CH}-\mathrm{CH}_{2} \mathrm{OH}\)