Question

The reactivities of methanol (I), 1 - propanol (II), 2 - butanol (III) and 2 - methyl-2- propanol (IV) towards sodium metal follow the order:

• A. I > II > III > IV
• B. IV > III > II > I
• C. I > IV > II > III
• D. IV > II > III > I

Answer 1

Answer: (A)

I > II > III > IV

Reaction of Na with alcohols occurs as follows :

2ROH + 2Na (s) → 2RONa + H2(g)

Alcohol Sodium Alkoxide

This is a test for the presence of Active hydrogen in alcohols.

And since primary alcohols are most acidic and tertiary being least acidic because of +I effect of alkyl group ,therefore primary alcohols react fastest with Na and tertiary alcohols will react slow as compared to that of 1o and 2o alcohols.

Reactivity order

1${}^o$ > 2${}^o$ > 3${}^o$

Hence, the correct option is $\text{A}$