At 298 K, the `[H_(3),O^(+)]` of a solution is `2 xx 10^(-9)` M. The nature of the solution is

Options

A. Acidic
B. Basic
C. Neutral
D. Can not be predicted

Answer

To determine the nature of the solution based on the concentration of hydronium ions \([H_3O^+]\), we can follow these steps:

### Step 1: Identify the given data
We are given:
- Temperature = 298 K
- Concentration of \([H_3O^+]\) = \(2 \times 10^{-9}\) M

### Step 2: Calculate the pH of the solution
The pH of a solution can be calculated using the formula:
\[ \text{pH} = -\log[H_3O^+] \]
Substituting the given concentration:
\[ \text{pH} = -\log(2 \times 10^{-9}) \]

### Step 3: Calculate the logarithm
Using properties of logarithms:
\[ \text{pH} = -(\log(2) + \log(10^{-9})) = -(\log(2) - 9) \]
Using the approximate value \(\log(2) \approx 0.301\):
\[ \text{pH} = -(0.301 - 9) = 9 - 0.301 = 8.699 \]
Thus, we can round it to:
\[ \text{pH} \approx 8.69 \]

### Step 4: Determine the nature of the solution
We know the following about pH:
- pH < 7 indicates an acidic solution
- pH = 7 indicates a neutral solution
- pH > 7 indicates a basic solution

Since we calculated the pH to be approximately 8.69, which is greater than 7, we conclude that the solution is basic.

### Final Answer
The nature of the solution is **basic**.

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