Answer:
Ok so To calculate the pH of an aqueous solution you need to know the concentration of the hydronium ion in moles per liter (molarity). The pH is then calculated using the expression:
pH = - log [H3O+].
Example: Find the pH of a 0.0025 M HCl solution. The HCl is a strong acid and is 100% ionized in water. The hydronium ion concentration is 0.0025 M. Thus:
pH = - log (0.0025) = - ( - 2.60) = 2.60
Step-by-step explanation:
The hydronium ion concentration can be found from the pH by the reverse of the mathematical operation employed to find the pH.
[H3O+] = 10-pH or [H3O+] = antilog (- pH)
Example: What is the hydronium ion concentration in a solution that has a pH of 8.34?
8.34 = - log [H3O+]
- 8.34 = log [H3O+]
[H3O+] = 10-8.34 = 4.57 x 10-9 M
On a calculator, calculate 10-8.34, or "inverse" log ( - 8.34).