Calculate the the ratio of conjugate base// weak acid required to prepare an aqueous solution of benzoic acid and sodium benzoate with `pH` of `4.5`. The acid dissociation constant of benzoic acid is `6.5 xx 10^(-5)`.

Explanation

To solve the problem of calculating the ratio of the conjugate base (sodium benzoate) to the weak acid (benzoic acid) required to prepare an aqueous solution with a pH of 4.5, we can follow these steps:

### Step 1: Understand the relationship between pH, pKa, and the ratio of conjugate base to weak acid.
For a buffer solution made from a weak acid and its conjugate base, the Henderson-Hasselbalch equation is used:
\[ \text{pH} = \text{pKa} + \log\left(\frac{[\text{Salt}]}{[\text{Acid}]}\right) \]
Where:
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