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Which of following is correct : -
A
Any aldehyde gives secondary alcohol on reduction
B
Reaction of vegetable oil with $H_2SO_4$ gives glycerin
C
$C_2H_5OH$, iodine with NaOH gives iodoform
D
Sucrose on reaction with NaCl gives invert sugar
Detailed Solution
Ethanol contains the $CH_3CH(OH)-$ group. With iodine and NaOH it is first oxidised to acetaldehyde and then gives a yellow precipitate of iodoform:
$C_2H_5OH + 4I_2 + 6NaOH \rightarrow CHI_3 + HCOONa + 5NaI + 5H_2O$; correct.
Reduction of aldehydes gives primary alcohols (ketones give secondary alcohols).
Glycerol is obtained by hydrolysis (saponification) of oils with alkali, not by reaction with $H_2SO_4$.
Invert sugar is obtained by hydrolysis of sucrose with dilute acid or the enzyme invertase, not with NaCl.
So the correct statement is that $C_2H_5OH$, iodine and NaOH give iodoform.
$C_2H_5OH + 4I_2 + 6NaOH \rightarrow CHI_3 + HCOONa + 5NaI + 5H_2O$; correct.
Reduction of aldehydes gives primary alcohols (ketones give secondary alcohols).
Glycerol is obtained by hydrolysis (saponification) of oils with alkali, not by reaction with $H_2SO_4$.
Invert sugar is obtained by hydrolysis of sucrose with dilute acid or the enzyme invertase, not with NaCl.
So the correct statement is that $C_2H_5OH$, iodine and NaOH give iodoform.