The correct decreasing order of pKa is from Chemistry Aldehydes,

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1021.

Methyl isocyanide on hydrolysis gives :

  • CH3NH2

  • HCOOH

  • CH3COOH

  • Both (a) and (b)


1022.

Cyclohexene on ozonolysis followed by reaction with zinc dust and water gives compound E. Compound Eon further treatment with aqueous KOH yields compound F. Compound F is


1023.

Maximum decarboxylation occurs in

  • CH3COOH

  • C6H5COOH

  • C6H5CH2COOH

  • CH3COCH2COOH


1024.

The correct increasing order of reactivity for the following molecules towards electrophilic aromatic substitution is

  • I < IV < II < III

  • I < IV < II < IV

  • I < III < II < IV

  • I < III < IV < II


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1025.

The corrcet decreasing order of pKb is 

  • I > II > III > IV

  • III > IV > II > I

  • II > III > IV > I

  • IV > II > I > III


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1026.

The correct decreasing order of pKa is

  • II > IV > I > III

  • IV > II > III > I

  • III > II > IV > I

  • IV > I > II > III


A.

II > IV > I > III

The correct decreasing order of pKa is II > IV > I > III. 

Weaker acids have higher pKa - OCH3 at meta-position exerts only -I effect, hence, it increases the acidity.

-I effect order : -NO2 > -OCH3 > -Cl

-CH3 has +I effect.


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1027.

The reagent used in Clemmensen's reduction is :

  • conc H2SO4

  • Zn-Hg / conc HCl

  • aq KOH

  • alc KOH


1028.

The product formed when hydroxylamine condenses with a carbonyl compound is called :

  • hydrazide

  • oxime

  • hydrazine

  • hydrazone


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1029.

Asssertion: CH3-C(COOC2H5)=CH-COOH is 3-carbethoxy-2-butenoic acid.

Reason : Principal functional group gets lowest number followed by double bond or triple bond.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.


1030.

Assertion : Aldol condensation can be catalysed both by acids and bases.

Reason : β-Hydroxy aldehydes or ketones readily undergo acid catalysed dehydration.

  • If both assertion and reason are true and reason is the correct explanation of assertion.

  • If both assertion and reason are true but reason is not the correct explanation of assertion.

  • If assertion is true but reason is false.

  • If both assertion and reason are false.


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