Statement $(I)$ : $2, 2 - d i m e t h y l p r o p a n a l$ undergoes Cannizzaro reaction with concentrated $N a O H$ .

Statement $(I I)$ : Cannizzaro is a disproportionation reaction.

Both the statements are true and statement

(I I)

is the correct explanation of statement

(I)

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Both statements are true but statement

(I I)

is not the correct explanation of statement

(I)

Right on! Give the BNAT exam to get a 100% scholarship for BYJUS courses

Statement

(I)

is true but statement

(I I)

is false.

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Statement

(I)

is false but statement

(I I)

is true.

No worries! We‘ve got your back. Try BYJU‘S free classes today!

Open in App

Solution

The correct option is
D
Both statements are true but statement $(II)$ is not the correct explanation of statement $(I)$ .
For Cannizzaro reaction absence of alpha hydrogen the necessary criterion
${(C H_{3})}_{3} C - C H O$ has no alpha hydrogen , hence it undergoes Cannizzaro reaction as it has not alpha hydrogen.
When 2,2-dimethyl propanal reacts with concentrated sodium hydroxide it is as follows
${(C H_{3})}_{3} C - C H O + C o n c e n t r a t e d N a O H u n d e r g o e s r e d u c t i o n - --------------- \to {(C H_{3})}_{3} C - C H_{3} O H$
${(C H_{3})}_{3} C - C H O + C o n c e n t r a t e d N a O H u n d e r g o e s o x i d a t i o n - --------------- \to {(C H_{3})}_{3} C - C O O N a$

Disproportionation reaction is one where oxidation and reduction takes place simultaneously , which happens in cannizaro reaction as shown above.

The steric effect of the $2$ methyl group hinders the aldol condensation reaction so it mainly undergoes Cannizzaro reaction. So, Assertion is correct but the reason is not the correct explanation.
However, note that it can undergo cross Aldol condensation with formaldehyde

Suggest Corrections

Similar questions

Q. Statement -

I

\to L = I \to ω

is always true for bodies of all shapes.
Statement-

II

\to τ = \frac{d \to L}{d t}

is always true in inertial frames.

Statement - I: $C l^{-} a n d C a^{2 +}$ are isoelectronic species.
Statement - II: Isoelectronic species should have same charges.

Statement - I: $M g^{2 +} a n d A l^{3 +}$ are isoelectronic but ionic radius $A l^{3 +}$ is less than that of $M g^{2 +}$ .
Statement - II: The effective nuclear charge on the outer-shell electrons in $A l^{3 +}$ is more than that in $M g^{2 +}$

Q. Statement I: Glucose gives a reddish-brown precipitate with Fehling's solution.
Statement I: Reaction of glucose with Fehling's solution gives CuO and gluconic acid.
(IIT-JEE, 2007)

Q. Statement I: LiCl is predominantly a convalent compound.
Statement II: Electronegativity difference between Li and Cl is too small.
(IIT-JEE, 1998)

Join BYJU'S Learning Program

Statement (I): 2,2−dimethylpropanal undergoes Cannizzaro reaction with concentrated NaOH.Statement (II): Cannizzaro is a disproportionation reaction.

Statement $(I)$ : $2, 2 - d i m e t h y l p r o p a n a l$ undergoes Cannizzaro reaction with concentrated $N a O H$ .

Statement $(I I)$ : Cannizzaro is a disproportionation reaction.