Hydrogen ion concentration in `mol//L` in a solution of `pH=5.4` will be:

Options

A. `3.98xx10^(-8)`
B. `3.88xx10^(-6)`
C. `3.68xx10^(-6)`
D. `3.98xx10^(-6)`

Explanation

To find the hydrogen ion concentration in a solution with a pH of 5.4, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the pH Definition**:
The pH of a solution is defined as the negative logarithm (base 10) of the hydrogen ion concentration \([H^+]\) in moles per liter (mol/L). The formula is given by:
\[ \text{pH} = -\log[H^+] \]

2. **Set Up the Equation**:
Given that the pH is 5.4, we can set up the equation:
\[ 5.4 = -\log[H^+] \]

3. **Rearrange the Equation**:
To find \([H^+]\), we first need to isolate the logarithm:
\[ -\log[H^+] = 5.4 \]
This implies:
\[ \log[H^+] = -5.4 \]

4. **Convert Logarithmic Form to Exponential Form**:
To find the hydrogen ion concentration, we convert the logarithmic equation into its exponential form:
\[ [H^+] = 10^{-5.4} \]

5. **Calculate the Value**:
Now, we can calculate \(10^{-5.4}\):
\[ [H^+] \approx 3.98 \times 10^{-6} \, \text{mol/L} \]

### Final Answer:
The hydrogen ion concentration in the solution is approximately:
\[ [H^+] \approx 3.98 \times 10^{-6} \, \text{mol/L} \]

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