Ease of esterification of following alcohol with HCOOH is
`(I) CH_(3)-CH_(2)OH" " (II) (CH_(3))_(2)CH-OH`
`(III) (CH_(3))_(3)C-OH`

Options

A. III gt II gt I
B. I gt II gt III
C. II gt I gt III
D. II gt III gt I

Answer

To determine the ease of esterification of the given alcohols with formic acid (HCOOH), we will analyze the structure of each alcohol and consider the concept of steric hindrance, which affects the rate of esterification.

### Step-by-Step Solution:

1. **Identify the Alcohols**:
- (I) Ethanol: CH₃-CH₂OH (1° alcohol)
- (II) Isopropanol: (CH₃)₂CHOH (2° alcohol)
- (III) Tert-Butanol: (CH₃)₃COH (3° alcohol)

2. **Understand Esterification**:
- The esterification reaction involves the reaction of an alcohol with a carboxylic acid (in this case, HCOOH) to form an ester and water. The reaction can be represented as:
\[ R'OH + RCOOH \rightarrow R'COOR + H₂O \]
- The reaction is typically catalyzed by an acid, such as sulfuric acid.

3. **Consider Steric Hindrance**:
- Steric hindrance refers to the crowding around the reactive site of a molecule. The more bulky the alcohol, the more steric hindrance there is, which can slow down the reaction.
- The order of steric hindrance for the given alcohols is:
- 1° alcohol (least hindered) < 2° alcohol < 3° alcohol (most hindered)

4. **Rank the Alcohols Based on Steric Hindrance**:
- Ethanol (1°) has the least steric hindrance, making it the most reactive towards esterification.
- Isopropanol (2°) has moderate steric hindrance, making it less reactive than ethanol but more reactive than tert-butanol.
- Tert-butanol (3°) has the most steric hindrance, making it the least reactive in esterification.

5. **Conclusion**:
- Based on the analysis, the order of ease of esterification with HCOOH is:
\[ \text{Ethanol (I)} > \text{Isopropanol (II)} > \text{Tert-Butanol (III)} \]

### Final Answer:
The ease of esterification of the alcohols with HCOOH is:
\[ \text{(I) Ethanol} > \text{(II) Isopropanol} > \text{(III) Tert-Butanol} \]