calculate the pH. A solution is formed mixing 12.0 mL of .120 M HBr with 22.0mL of .180 M HCl
Both are strong acids.
mols HBr = M x L = ?
mols HCl = M x L = ?
Total mols = sum of the two.
M acid = total mols/total L and that is the molarity of the (H^+).
Then pH = -log(acid)
To calculate the pH of a solution formed by mixing two acids, you need to consider the concentrations of the acids and their dissociation constants. In this case, you have two acids, HBr and HCl, with known concentrations.
Step 1: Determine the moles of each acid
To calculate the moles of each acid, you need to use the formula:
moles = concentration (in M) × volume (in L)
For HBr:
moles of HBr = 0.120 M × 0.012 L = 0.00144 moles
For HCl:
moles of HCl = 0.180 M × 0.022 L = 0.00396 moles
Step 2: Determine the total moles of acid in the solution
To calculate the total moles of acid in the solution, you need to add the moles of HBr and HCl:
total moles = moles of HBr + moles of HCl
total moles = 0.00144 moles + 0.00396 moles
total moles = 0.00540 moles
Step 3: Determine the molarity of the resulting solution
To calculate the molarity of the resulting solution, divide the total moles by the total volume:
resulting molarity = total moles / total volume
resulting molarity = 0.00540 moles / (12.0 mL + 22.0 mL)
resulting molarity = 0.00540 moles / 0.0340 L
resulting molarity = 0.1588 M
Step 4: Calculate the pOH
The pOH of a solution can be calculated using the formula:
pOH = -log10(OH- concentration)
Since HCl and HBr are strong acids, they dissociate completely in water, resulting in the formation of H+ ions. Therefore, you can assume that the concentration of H+ ions is equal to the molarity of the resulting solution.
pOH = -log10(0.1588 M) = 0.8002
Step 5: Calculate the pH
The pH of a solution can be calculated using the formula:
pH = 14 - pOH
pH = 14 - 0.8002
pH ≈ 13.2
Therefore, the pH of the solution formed by mixing 12.0 mL of 0.120 M HBr with 22.0 mL of 0.180 M HCl is approximately 13.2.