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CBSE Class 12 · 2011 · Delhi · Aldehydes Ketones and Carboxylic AcidsLong Answer

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i) Describe the following, giving linked chemical equations:
a) Cannizzaro reaction b) decarboxylation
ii) Complete the three chemical equations shown in the figure (parts a, b, c).
Structure (ii)(a)
(ii)(a)
Structure (ii)(b)
(ii)(b)
Structure (ii)(c)
(ii)(c)

Answer: (i)(a) Disproportionation of no-α-H aldehyde in conc. alkali; (b) RCOONa + NaOH/CaO, Δ → RH. (ii) Per the printed lines.

Solution

(i)(a)

(the alkoxide-hydride transfer oxidises one molecule, reduces the other).
(b)

(ii) Complete each displayed equation by its standard pattern — the two printed members (substrate/reagent or reagent/product) fix the third.

CBSE Class 12 Board · 2011 · Delhi · Subjective

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