Phenol associates in water to double molecules. The values of observed and calculated molecular weight of phenol are `161.84` and `94` , repectively. The degree of association of phenol will be
a. 60% , b. 84% , c. 45% , d. 80%

Explanation

To determine the degree of association of phenol in water, we can follow these steps:

### Step 1: Understand the association of phenol
Phenol can associate in water to form dimers. This means that two phenol molecules can combine to form one dimer. Therefore, if we denote the degree of association as \( \alpha \), the number of phenol molecules that remain unassociated will be \( 1 - \alpha \).

### Step 2: Determine the van 't Hoff factor (i)
The van 't Hoff factor \( i \) for a substance that associates can be expressed as:
\[
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