The pH of a solution is the negative logarithm to the base 10 of its hydrogen ion concentration in

Options

A. Moles per litre
B. Millimoles per litre
C. Micromoles per litre
D. Nanomoles per litre

Explanation

To find the pH of a solution based on its hydrogen ion concentration, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Definition of pH**:
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).

\[ \text{pH} = -\log_{10}([H^+]) \]

2. **Identify the Hydrogen Ion Concentration**:
Determine the concentration of hydrogen ions in the solution. This is typically given in moles per liter (mol/L). If the concentration is given in millimoles per milliliter (mmol/mL), convert it to moles per liter by using the conversion factor:
\[ 1 \, \text{mmol/mL} = 1 \, \text{mol/L} \times 10^{-3} \]

3. **Calculate the pH**:
Substitute the hydrogen ion concentration into the pH formula. For example, if the concentration of hydrogen ions is \(1 \times 10^{-3} \, \text{mol/L}\):
\[ \text{pH} = -\log_{10}(1 \times 10^{-3}) \]

4. **Perform the Logarithmic Calculation**:
Using logarithmic properties, we can simplify:
\[ \text{pH} = -(-3) = 3 \]

5. **Final Result**:
The pH of the solution is 3.