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Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

The molecular formula of ethanol is :

  1. $(CH _3) _2 CHOH$
  2. $C _2 H _5 OH$
  3. $CH _3 OH$
  4. $CH _3 CH _2 CH _2 OH$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

$(CH _3) _2CHOH$ is 2-propanol or isopropyl alcohol, $CH _3OH$ is methanol, $CH _3CH _2CH _2OH$ is 1- propanol or isopropyl alcohol.

The compound in option B is ethanol. It is hydroxyl derivative of ethane.

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

Write the IUPAC name of the given compound:

$\begin{matrix} HO-C{ H } _{ 2 } \ - & CH &-C{ H } _{ 2 }-OH \  & | &  \  & C{ H } _{ 3 } &  \end{matrix}$

  1. 2-Methylpropane-1,3-diol

  2. 2-Methylpropan-1,3-dial

  3. 1-Hydroxy-2-methylpropan-1-ol

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

The given compound can be numbered from left to right or vice versa. At the 2nd position, there is a methyl group and is designated as 2-Methyl. 


The parent carbon chain contains 3 carbon atoms resembling propane and at the positions 1 and 3, there's the hydroxyl group designated as 1,3-diol. 


So the IUPAC name of the given compound is 2-Methylpropane-1,3-diol.


The answer is option A.

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

What is the $IUPAC$ name of the following compound?


$CH _{3} - CH _{2} - CH _{2} - OH$

  1. Propan-1-ol

  2. Propan-2-ol

  3. Propane-1-ol

  4. Ethane-2-ol
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

In this compound, the number of carbon atoms is 3. So, the parent alkane is propane. 


The functional group present is $-OH$ i.e alcohol. $-OH$ is present at the first carbon atom 

Thus the IUPAC name is Propan - 1 - ol.

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

Identify 'C' in the following reaction. 


$C _2H _5Br       \overset{KCN}  {\longrightarrow} A \overset{H^+ H _2O}   {\longrightarrow} B \overset{LiAlH _4}{\longrightarrow} C$

  1. $Propan - 1 - ol$
  2. $Propanone$
  3. $2 - Ethyl - 3 - pentanone$
  4. $Propanal$
Reveal answer Fill a bubble to check yourself
A Correct answer
Explanation

C2H5Br + KCN -> C2H5CN (Propanenitrile). Hydrolysis -> C2H5COOH (Propanoic acid). Reduction with LiAlH4 -> C2H5CH2OH (Propan-1-ol).

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

The IUPAC name for $CH _3CH(OH)CH _2C(CH _3) _2OH$ is:

  1. 1, 1-dimethyl-1,3-butanediol

  2. 2-methyl-2,4 pentanediol

  3. 4-methyl-2 4-pentanediol

  4. 1,3,3- trimethyl 1-1,3-propanediol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

The compound has 2 alcohol groups at C-2 positions on both the sides. From this point we can not say from where to start numbering. But if we number from right hand side there is also a methyl group at C-2 position. So we start number from right hand side.
Since there are two alcoholic group, we use suffix "diol"
Thus IUPAC name is: 2-Methyl-2,4 pentanediol

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

IUPAC name of the compound $CH _3-CH(CH _2CH _3)-CH _2-CH(OH)-CH _3$ is:

  1. 4-Ethyl-2-pentanol

  2. 4-Methyl-2-hexanol

  3. 2-Ethyl-2-pentanol

  4. 3-Ethyl-2-hexanol
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation

Longest carbon chain has 6 atoms. We number from right hand side as alcohol group at C-2 gets least number in this case and suffix used for alcohol is "-ol". Methyl group is present at C-4 position.

Thus, IUPAC name is 4-Methyl-2-hexanol.

Multiple choice chemistry derivatives of hydrocarbons alcohol nomenclature of alcohols and phenols introduction to alcohols

The general formula for alcohol series is $C _nH _{2n+1}OH$. Which is the formula for alcohol contains four carbon?  

  1. $C _5H _{11}OH$
  2. $C _4H _{9}OH$
  3. $C _4H _{8}OH$
  4. $C _3H _{8}OH$
Reveal answer Fill a bubble to check yourself
B Correct answer
Explanation
The general formula for alcohol series is $C _nH _{2n+1}OH$. The formula for alcohol contains four carbon atoms is
$C _nH _{2n+1}OH$ $=C _4H _{2(4)+1}OH$ $=C _4H _{8+1}OH$ $=C _4H _{9}OH$.
Multiple choice methods of purification of organic compounds methods of purification - organic compounds organic chemistry - some basic principles and techniques organic chemistry : some basic principles and techniques chemistry biochemical techniques

Which one of the following reagent is useful for separating aniline from nitrobenzene?

  1. $ aq. NaHCO _3 $
  2. $ aq. NaHSO _3 $
  3. $ aq. HCl $
  4. $dil. H _2SO _4 $
Reveal answer Fill a bubble to check yourself
C Correct answer
Explanation

The reagent selected should be such that only one of components to be separated, reacts with it.


Aniline $+$ aq, HCl $\rightarrow$ salt, which is soluble in water
Nitrobenzene $+$ aq. HCl$\rightarrow$ no reaction.

Therefore, aq. HCL is used to separate aniline and nitrobenzene.