What is the pH of a solution of HNO3 if the hydrogen ion concentration is 2.5 × 10-2 M?

To determine the pH of the solution, we can use the formula for pH, which is defined as the negative logarithm (base 10) of the hydrogen ion concentration. The formula is:

[ \text{pH} = -\log[\text{H}^+] ]

Given a hydrogen ion concentration of (2.5 \times 10^{-2} , \text{M}), we can substitute this value into the formula to find the pH:

1. Calculate the logarithm:

[ \log(2.5 \times 10^{-2}) ]

2. Using logarithmic rules, this can be expressed as:

[ \log(2.5) + \log(10^{-2}) = \log(2.5) - 2 ]

3. We find that ( \log(2.5) ) is approximately (0.3979). Therefore:

[ \log(2.5 \times 10^{-2}) \approx 0.3979 - 2 = -1.6021 ]

4. Now, taking the negative value gives:

[ \text{pH} \