Calculate [H3O+] for a solution of hydrobromic acid for which pH = 5.79. Be sure your answer has the correct number of significant figures.

1 answer

To calculate the concentration of hydronium ions \([\text{H}_3\text{O}^+]\) from the pH, you can use the following formula:

\[ [\text{H}_3\text{O}^+] = 10^{-\text{pH}} \]

Given that the pH is 5.79, we can substitute this value into the equation:

\[ [\text{H}_3\text{O}^+] = 10^{-5.79} \]

Now, performing the calculation:

\[ [\text{H}_3\text{O}^+] \approx 1.64 \times 10^{-6} \text{ M} \]

The pH value of 5.79 has three significant figures, so our final answer for \([\text{H}_3\text{O}^+]\) should also reflect three significant figures:

\[ [\text{H}_3\text{O}^+] = 1.64 \times 10^{-6} \text{ M} \]