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  1. 1^{0} amine with same number of carbons

  2. 1^{0} amine with one carbon less

  3. 2^{0} amine with one carbon less

  4. 1^{0} amine with one carbon more

option 2

 

Engineering
137 Views   |  

Thiol group is present in :

  • Option 1)

    Cytosine

  • Option 2)

    Cystine

  • Option 3)

    Cysteine

  • Option 4)

    Methionine

 
Cysteine contain thiol (SH) group.  Option 1) Cytosine Incorrect Option 2) Cystine Incorrect Option 3) Cysteine Correct Option 4) Methionine Incorrect
Engineering
295 Views   |  

An organic compound A upon reacting with NH3 gives B .On heating ,B gives C .C in presence of KOH reacts  With Br2 to give CH3CH2NH2. A is :

  • Option 1)

    CH_{3}CH_{2}COOH

  • Option 2)

    CH_{3}COOH

  • Option 3)

    CH_{3}CH_{2}CH_{2}COOH

  • Option 4)

 
As we learnt in  Hofmann Bromamide Degradation - Amines ( only primary ) can also be prepared by Hofmann degradation. In this method the amine will have one carbon atom less than the amide.  - wherein   Option 1) This option is correct Option 2) This option is incorrect Option 3) This option is incorrect Option 4) This option is incorrect
Engineering
476 Views   |  

 The final product formed when Methyl  amine is treated with NaNO2 and HCl is

  • Option 1)

      Diazomethane  
     

     

  • Option 2)

      Methylalcohol   
     

  • Option 3)

     Methylcyanide   
     

  • Option 4)

    Nitromethane  

 
As we learnt in  Reaction with Nitrous Acid Primary Amines - Primary amines react with nitrous acid to produce diazonium ion. - wherein     The values of ionization potential of an element decrease as the atomic size increases. Also, removal of electron from half or full filled atoms require more energy than expected with maximum in noble gases. Finally, IE increases along a period and...
Engineering
98 Views   |  

Which of the following is not used to convert RCHO into RCH_{2}OH?

  • Option 1)

    H_{2}/Pd

  • Option 2)

    LiAlH_{4}

  • Option 3)

    NaBH_{4}

  • Option 4)

    Reaction with RMgX followed by hydrolysis

 
As we learnt in Reaction of Grignard reagent with aldehyde - With methanol yields primary alcohol, with all other aldehydes produces secondary alcohols - wherein    Except methanal, all other aldehyde with grignard reagent produces secondary alcohol. Rest all are reducing agent which reduces RCHO to RCH2OH Option 1) Option is incorrect Option 2) Option is incorrect Option 3) Option is...
Engineering
132 Views   |  

Which has lowest solubility in water?

  • Option 1)

    CH_{3}CH_{2}CH_{2}CH_{2}OH

  • Option 2)

     

                    CH_{3}

                      |

    CH_{3}-CH-CH_{2}OH

  • Option 3)

    HOH_{2}C-CH_{3}

  • Option 4)

    C_{6}\: H_{5}\: CH_{2}\: CH_{2}OH

 
As we learnt in Physical properties of alcohol - –  Lower alcohols are colourless liquids but higher alcohols are colourless waxy solids. –  Increase in boiling point with increase in number of carbon atoms. –  Boiling point decrease with increase of branching in carbon atom. –  Solubility decreases with increase in the size of alkyl groups. -      is least soluble due to its size Option...
Engineering
117 Views   |  

Which gives a Ketone with a Grignard reagent?

  • Option 1)

    Formaldehyde

  • Option 2)

    Ethyl alcohol

  • Option 3)

    methyl cyanide

  • Option 4)

    methyl iodide

 
As we learnt in Ketone formation from nitriles - Nitrile with Grignard reagent in the presence of ether followed by hydrolysis yields ketone. - wherein     Option 1) Formaldehyde Option is incorrect Option 2) Ethyl alcohol Option is incorrect Option 3) methyl cyanide Option is Correct Option 4) methyl iodide Option is incorrect
Engineering
78 Views   |  

The end product B in the sequence of reactions

R- \times\overset{CN^{-}}{\rightarrow}A\overset{NaOH}{\rightarrow}B    is:

  • Option 1)

    An alkene

  • Option 2)

    A carboxylic Acid

  • Option 3)

    Sodium Salt of Carboxylic Acid

  • Option 4)

    A ketone

 
As we learnt in Hydrolysis of nitriles (cyanides) - Nitriles on heating with acid or base yield carboxylic acid via amides as intermediate. - wherein     Option 1) An alkene Incorrect Option 2) A carboxylic Acid Incorrect Option 3) Sodium Salt of Carboxylic Acid correct Option 4) A ketone Incorrect
Engineering
234 Views   |  

The decreasing rate of esterification of primary, secondary and tertiary alcohols is

  • Option 1)

    1^{\circ}>2^{\circ}>3^{\circ}

  • Option 2)

    3^{\circ}>2^{\circ}>1^{\circ}

  • Option 3)

    1^{\circ}>3^{\circ}>72^{\circ}

  • Option 4)

    2^{\circ}>3^{\circ}>1^{\circ}

 
As we learnt in Fischer - Speier Esterification - Reaction of alcohols with carboxylic acid. - wherein    Alcohols react with carboxylic acid to form esters. Rate of esterification 1° alcohol > 2° alcohol > 3° alcohol   Option 1) This option is correct Option 2) This option is incorrect Option 3) This option is incorrect Option 4) This option is incorrect
Engineering
107 Views   |  

Pleasant odour of common fruits is due to:

  • Option 1)

    Alcohol

  • Option 2)

    Fats

  • Option 3)

    sugars

  • Option 4)

    Esters

 
As we learnt in Fischer - Speier Esterification - Reaction of alcohols with carboxylic acid. - wherein    Pleasant odour of fruits is due to esters produce by the reaction of alcohols with carboxylic acids   Option 1) Alcohol This option is incorrect Option 2) Fats This option is incorrect Option 3) sugars This option is incorrect Option 4) Esters This option is correct
Engineering
174 Views   |  

pKa is more for

  • Option 1)

  • Option 2)

  • Option 3)

  • Option 4)

 
As learnt in Effects of substituents on acidity of phenols - 1.  Electron withdrawing group like    2.  Electron donating group like     - wherein 1.  Increase the acidic strength of phenol. 2.  Decrease the acidic strength of phenol.     Reaction with Nitrous Acid Primary Amines - Primary amines react with nitrous acid to produce diazonium ion. - wherein      Acidity increases down the...
Engineering
94 Views   |  

Paraldehyde is

  • Option 1)

    A trimer of formaldehyde

  • Option 2)

    A trimer of Acetaldehyde

  • Option 3)

    A hexmer of formaldehyde

  • Option 4)

    A hexamer of acetaldehyde

 
As we learnt in Polymerization of acetaldehyde - –  Three molecules of acetaldehyde form paraldehyde used as hypnotic (sleep-inducing drug) –  Four molecules of acetaldehyde form metaldehyde used as fuels in lamps. - wherein    3 molecules of acetaldehyde forms paraldehyde Option 1) A trimer of formaldehyde This option is incorrect Option 2) A trimer of Acetaldehyde This option is...
Engineering
119 Views   |  

Main product of the reaction CH_{3}CONH_{2}+HNO_{2}\rightarrow  is:

  • Option 1)

    CH_{3}COOH

  • Option 2)

    CH_{3}CH_{2}NH_{2}

  • Option 3)

    CH_{3}NH_{2}

  • Option 4)

    CH_{3}COONH_{4}

 
As we learnt in Hydrolysis of Cyanide - The alkyl cyanides are hydrolysed by acid or alkali to the corresponding acid via the intermediate formation of an amide. - wherein     Option 1) This solution is correct. Option 2) This solution is incorrect. Option 3) This solution is incorrect. Option 4) This solution is incorrect.
Engineering
473 Views   |  

If Phenyl magnesium bromide and acetaldehyde are reactants, product formed after hydrolysis would be

  • Option 1)

    Benzyl alcohol

  • Option 2)

    I-Phenylethanol

  • Option 3)

    2-Phenylethanol

  • Option 4)

    Acetone

 
As we learnt in Reaction of Grignard reagent with aldehyde - With methanol yields primary alcohol, with all other aldehydes produces secondary alcohols - wherein    Reaction of aldehyde (acetaldehyde) with grignard reagent (phenyl magnesium bromide) yields alcohol after hydrolysis.   Option 1) Benzyl alcohol Incorrect Option 2) I-Phenylethanol Correct Option...
Engineering
122 Views   |  

Highest rate of esterification with alcohols will be given by

  • Option 1)

    HCOOH

  • Option 2)

    (CH_{3})_{2} CHCOOH

  • Option 3)

    (CH_{3})_{3}CCOOH

  • Option 4)

    CH_{3}COOH

 
As we learnt in Esterification of carboxylic acid - ⇒ Carboxylic acid with alcohols or phenols forms esters in the presence of catalyst H2SO4 / HCl ⇒  It's a kind of nucleophilic acyl substitution. ⇒  Involves cleavage of C - OH bond. - wherein    Carboxylic acids with alcohols from esters Nucleophiles react more readily with unhindered carbonyl groups. Option 1) HCOOH This solution is...
Engineering
102 Views   |  

Formalin is

  • Option 1)

    Formaldehyde

  • Option 2)

    Formaldehyde +nethanol

  • Option 3)

    formaldehyde +methanol+water

  • Option 4)

    Formaldehyde+water

 
As we learnt in Methanol (wood spirit) - Highly poisonous, used in paints, varnishes & for making formaldehyde.  - wherein   Formation is 37% aqueous solution of formaldeyde with 10-15% methanol. Methanol or wood spirit is highly poisonous and is added in formation to slow down the polymerisation of formaldehyde. Option 1) Formaldehyde This solution is incorrect Option 2) Formaldehyde...
Engineering
95 Views   |  

Consider the following reactions:

CH_{3}COOH\overset{CaCO_{3}}{\rightarrow}A\overset{Heat}{\rightarrow}B

Compound B is:

  • Option 1)

    An ether

  • Option 2)

    Alcohol

  • Option 3)

    Aldehyde

  • Option 4)

    A Ketone

 
As we learnt in  Ketone formation from calcium salts - Distillation of calcium salt of fatty acid. - wherein     Option 1) An ether This option is incorrect. Option 2) Alcohol This option is incorrect. Option 3) Aldehyde This option is incorrect. Option 4) A Ketone This option is correct.
Engineering
448 Views   |  

An aldehyde can be distinguished from a Ketone by the use of reagent

  • Option 1)

    Grignard reagent

  • Option 2)

    Schiff's reagent

  • Option 3)

    Hydroxylomine

  • Option 4)

    Hydrazine

 
As we learnt in  Oxidation of aldehydes with Tollen's reagent / silver mirror test - –  Distinguish aldehydes from ketones .–  Tollen's reagent = ammoniacal silver nitrate solution.   - wherein    and Oxidation of aldehydes with Fehling's solution - –  Fehling solution A is aqueous copper sulphate, Fehling solution B is alkaline sodium potassium tartrate (Rochelle salts) –  Distinguished...
Engineering
81 Views   |  

Aldoximes on reduction with LiAlH_{4}    or    Na/C_{2}H_{5}OH    give:

  • Option 1)

    1o Amines

  • Option 2)

    2o Amines

  • Option 3)

    3o Amines

  • Option 4)

    Quaternary salts

 
As we learnt in  By Reduction of Oximes - Oximes can be reduced to primary amines by using Na in ethanol solvent. - wherein    Reducing aldoximes with      Option 1) 1o Amines This option is correct. Option 2) 2o Amines This option is incorrect. Option 3) 3o Amines This option is incorrect. Option 4) Quaternary salts This option is incorrect.
Engineering
95 Views   |  

3-methyl 2-butanol\overset{HBr}{\rightarrow}Product (X) the major product of the above reaction is 

  • Option 1)

    2-bromo 3-methyl butane

  • Option 2)

    2-bromo 2-methyl butane

  • Option 3)

    1-bromo 2-methylbutane

  • Option 4)

    None of these

 
As we learnt in  Alcohols reaction with hydrogen halides - Forms alkyl halides. - wherein     Option 1) 2-bromo 3-methyl butane This option is incorrect. Option 2) 2-bromo 2-methyl butane This option is correct. Option 3) 1-bromo 2-methylbutane This option is incorrect. Option 4) None of these This option is incorrect.
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