Download App

6. Haloalkanes and Haloarenes — Chemistry STD 12 Science — Question

CBSE BoardEnglish MediumSTD 12 ScienceChemistry6. Haloalkanes and Haloarenes1 Mark
MCQ
Correct reactivity order of Alkyl halide towards dehydrohalogenation-
  • ✓
    $3^o > 2^o > 1^o$
  • B
    $1^o > 2^o > 3^o$
  • C
    $2^o > 1^o > 3^o$
  • D
    $1^o > 3^o > 2^o$
✓

Answer

Correct option: A.
$3^o > 2^o > 1^o$
a
According to Saytzeff rule, any alkyl halide that gives a more highly substituted (more stable) alkene undergoes dehydrohahyenation faster than the one which gives a less highly substituted (less stable) alkane. Thus, the case of dehydrohalogenation of different alkyl halides having the same halogen decreases in the order: $3^{\circ} (tertiary) > 2^{\circ} (secondary) > 1^{\circ} (Primary)$

Need a full question paper?

Generate a complete, print-ready paper with questions like this in minutes — across 16+ boards, with answer keys.

Start Generating Free

Explore more

More "M.C.Q (1 Marks)" from 6. Haloalkanes and Haloarenes→6. Haloalkanes and Haloarenes — all question types→Chemistry STD 12 Science question papers→CBSE Board STD 12 Science question papers→CBSE Board question paper generator→

Similar questions

The unit of velocity constant in case of zero order reaction is
→
The enzymes are substances which:
→
A tetra-atomic molecule $(A)$ on reaction with nitrogen $(I)$ oxide, produces two substances $(B)$ and $(C).$ $(B)$ is a dehydrating agent in its monomeric form while substance $(C)$ is a diatomic gas which shows almost inert behaviour. The substances $(A)$ and $(B)$ and $(C)$ respectively will be
→
Which of the following isomers of $C_8H_9NO$ is the weakest base ?
→
The crystal field splitting energy for octahedral $\left( {{\Delta _0}} \right)$ and tetrahedral $\left( {{\Delta _t}} \right)$ complexes is related as
→
A standard hydrogen electrode has zero electrode potential because
→
The close$-$packing sequence $\text{ABAB} ......$ represents:
→
Given below are two statements: one is labelled as Assertion $(A)$ and the other is labelled as Reason $(R)$.

Assertion $(A)$ : $\mathrm{PH}_3$ has lower boiling point than $\mathrm{NH}_3$.

Reason $(R)$ : In liquid state $\mathrm{NH}_3$ molecules are associated through vander waal's forces, but $\mathrm{PH}_3$ molecules are associated through hydrogen bonding. In the light of the above statements, choose the most appropriate answer from the options given below:

→
$A ( g ) \rightarrow 2 B ( g )+ C ( g )$ is a first order reaction. The initial pressure of the system was found to be $800\,mm\,Hg$ which increased to $1600\,mm\,Hg$ after $10\,min$. The total pressure of the system after $30\,min$ will be $.........\,mm\,Hg$. (Nearest integer)
→
Inertness of ${N_2}$ gas is due to
→