Final answer:
To calculate the pH of a solution formed by mixing two strong acids, begin by finding the concentration of H+ ions in each acid solution. Add the moles of H+ ions together, divide by the total volume of the final solution, and take the negative logarithm to find the pH. In this case, the pH of the solution formed by mixing 14.0 mL of 0.130 M HBr with 20.0 mL of 0.210 M HCl is approximately 2.75.
Step-by-step explanation:
To calculate the pH of a solution formed by mixing two strong acids, we can use the equation:
pH = -log[H+]
First, we need to find the concentration of H+ ions in the final solution. To do this, we calculate the moles of H+ ions from each acid solution, then add them together. The total volume of the final solution is the sum of the volumes of the two individual acid solutions. Finally, we divide the moles of H+ ions by the total volume to get the concentration of H+ ions, and then take the negative logarithm to find the pH.
In this case, we have:
Concentration of H+ ions from HBr solution = (14.0 mL)(0.130 M) = 1.82 mmol
Concentration of H+ ions from HCl solution = (20.0 mL)(0.210 M) = 4.20 mmol
Total moles of H+ ions = 1.82 mmol + 4.20 mmol = 6.02 mmol
Total volume of the final solution = 14.0 mL + 20.0 mL = 34.0 mL = 0.034 L
Concentration of H+ ions in the final solution = (6.02 mmol)/(0.034 L) = 177.1 mM
pH = -log[H+] = -log(177.1 × 10-3) = 2.75