Tag: hydrocarbons

Quizzes (8) Questions (34)

Questions Related to hydrocarbons

Multiple choice chemistry hydrocarbons introduction to alkenes - ethyne acetylene alkynes

Acetylene may be prepared using Kolbes electrolytic method employing:

  1. Pot. acetate

  2. Pot. succinate

  3. Pot. fumarate

  4. None of these
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Acetylene may be prepared using Kolbes electrolytic method employing potassium fumerate. Acetylene is obtained at anode. The solution is basic due to formation of KOH at cathode.
$\displaystyle  (CHCOONa) _2 \xrightarrow {Electrolysis} C _2H _2+2CO _2+2KOH + H _2$

Multiple choice chemistry hydrocarbons introduction to alkenes - ethyne acetylene alkynes

$C _{2}H _{2}$ on reaction with Na followed by reaction with $C _{2}H _{5}I$ gives 'X'. The molecular formula of 'X' is:

  1. $C _{2}H _{6}$
  2. $C _{4}H _{8}$
  3. $C _{4}H _{6}$
  4. $C _{3}H _{6}$
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

Reaction: $CH \equiv CH \xrightarrow{Na} Na - C \equiv  CH \xrightarrow{C _2H _5I} C _2H _5 - C \equiv  CH + NaI$


Hence, the correct option is $C$

Multiple choice chemistry hydrocarbons introduction to alkenes - ethyne acetylene alkynes

1, 1, 2, 2-Tetra bromoethane $\xrightarrow {Zn}A$ $\xrightarrow{red hot \ tube}B$,


 Then B is:

  1. Acetylene

  2. Ethylene

  3. Ethane

  4. Benzene
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

$H-\overset{Br}{\overset{|}{\underset{Br}{\underset{|}{C}}}}-\overset{Br}{\overset{|}{\underset{Br}{\underset{|}{C}}}}-H\xrightarrow[\triangle]{2n}H-C\underset{(A)}{\equiv} C-H\xrightarrow{ red hot \ tube} C _6H _6$


Option D is correct.

Multiple choice chemistry hydrocarbons introduction to alkenes - ethyne acetylene alkynes

$H-C\equiv C-H+NaNH _{2}\longrightarrow A\overset{2 \ mole \ CH _3I}{\longrightarrow}B$


Then B is :

  1. 1-Butyne

  2. 2-Butyne

  3. 2-Pentyne

  4. Propyne
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Reaction of process:
$CH\equiv CH+2NaNH _2\rightarrow NaC\equiv CNa\xrightarrow {2 mole CH _3I} CH _3CH\equiv CHCH _3$


Option B is correct.

Multiple choice chemistry hydrocarbons introduction to alkenes - ethyne acetylene alkynes

$X+2Zn\overset{Alcohol}{\rightarrow}H-C\equiv C-H$ 


Here X is :

  1. 1, 1-Dibromoethane

  2. 1, 2-Dibromoethane

  3. Dibromo ethane

  4. 1, 1, 2, 2-Tetrachloroethane
Reveal answer Fill a bubble to check yourself
D Correct answer
Explanation

This is dehalogenation process:


$CHCl _2-CHCl _2+2Zn\overset{Alcohol}{\longrightarrow}H-C\equiv C-H$

Option D is correct.