What is the pH of a solution obtained by adding 145mL of 0.575M HCl to 493mL of a HNO3 solution with a pH of 1.39?
pH = -log(HNO3)
-1.39 = log(HNO3)
I found HNO3 approximately 0.05 but you need to do it more accurately.
Then mol HNO3 = M x L = ?
mols HCl = M x L
total mols H^+ = mols HCl + mols HNO3.
volume = 145 mL + 493 mL = ?
M new solution = total mols/total liters.
Then pH = -log(H^+)
To determine the pH of the resulting solution, we need to first calculate the combined concentration of H+ ions in the solution.
Step 1: Calculate the moles of HCl:
To find the moles of HCl, we can use the equation:
moles = concentration (mol/L) x volume (L)
moles of HCl = 0.575 mol/L x 0.145 L
moles of HCl = 0.08375 mol
Step 2: Calculate the moles of HNO3:
The concentration of HNO3 is not provided, only the pH. To find the concentration, we need to convert the pH to [H+] concentration using the formula:
[H+] = 10^(-pH)
[H+] = 10^(-1.39)
[H+] = 0.0455 mol/L
moles of HNO3 = 0.0455 mol/L x 0.493 L
moles of HNO3 = 0.02247 mol
Step 3: Calculate the total moles of H+ ions in the solution:
Total moles of H+ = moles of HCl + moles of HNO3
Total moles of H+ = 0.08375 mol + 0.02247 mol
Total moles of H+ = 0.10622 mol
Step 4: Calculate the final volume of the solution:
The final volume is the sum of the initial volumes of the two solutions:
Final volume = 145 mL + 493 mL
Final volume = 638 mL
Step 5: Calculate the concentration of H+ ions in the resulting solution:
The concentration of H+ ions is given by:
[H+] concentration = moles of H+/final volume
[H+] concentration = 0.10622 mol / 0.638 L
[H+] concentration = 0.1666 mol/L
Step 6: Calculate the pH of the solution:
pH = -log[H+] concentration
pH = -log(0.1666)
pH = 0.778
Therefore, the pH of the resulting solution obtained by adding 145 mL of 0.575 M HCl to 493 mL of an HNO3 solution with a pH of 1.39 is approximately 0.778.
To find the pH of the resulting solution, we need to calculate the concentration of H+ ions in the solution.
First, let's find the moles of HCl and HNO3 added to the solution.
Moles of HCl = volume (in liters) × molarity
= 0.145 L × 0.575 M
= 0.083375 moles
The moles of HNO3 added will depend on its concentration. Given that we only have the pH of the HNO3 solution, we need to convert it to concentration in order to calculate the moles.
When given the pH of a solution, we can use the following formula to calculate the concentration of H+ ions:
[H+] = 10^(-pH)
Thus,
[H+] (HNO3 solution) = 10^(-1.39)
= 0.0416 M
Now, let's calculate the moles of HNO3:
Moles of HNO3 = volume (in liters) × concentration
= 0.493 L × 0.0416 M
= 0.020452 moles
The total moles of H+ ions in the solution is the sum of the moles of HCl and HNO3:
Total moles of H+ ions = moles of HCl + moles of HNO3
= 0.083375 moles + 0.020452 moles
= 0.103827 moles
To find the concentration of H+ ions in the solution, divide the total moles by the total volume of the solution in liters:
Concentration of H+ ions = total moles / total volume (in liters)
= 0.103827 moles / (0.145 L + 0.493 L)
= 0.103827 moles / 0.638 L
= 0.16248 M
Finally, we can calculate the pH of the solution using the formula:
pH = -log[H+]
pH = -log(0.16248)
= 0.789
Therefore, the pH of the resulting solution is approximately 0.789.