Honors Chemistry
Name: ___________________________________________
Date: _________
Calculating pH, pOH, [H+] and [OH-] for Strong Acids and Bases
Strong Acids:
Strong acids completely dissociate into ions in aqueous solution. Therefore, calculating the pH
of a solution of a strong monoprotic acid is straightforward because [H+] equals the original
concentration of the acid.
1) What is the pH of a 0.20 M solution of HNO3?
2) An aqueous solution of HCl has a pH of 1.12. What is the concentration of this acid?
Strong Bases:
Strong bases also completely dissociate into ions in aqueous solution. Thus, calculating the pH
of their solutions is also straightforward.
1) What is the pH of a 0.028 M NaOH solution?
2) What is the pH of a 0.0011 M Ca(OH)2 solution?
3) What is the concentration of a solution of KOH for which the pH is 11.89?
4) What is the concentration of a solution of Ca(OH)2 for which the pH is 11.68?
Molarity (M):
The concentration of acids and bases is measured using molarity (M). Give the formula for
molarity in the space below:
1) Calculate the pH of a solution containing 1.52 g of HNO3 in 575 mL of solution.
2) Calculate the pH when 2.250 g of LiOH are dissolved in 250.0 mL of solution.
Diluting Strong Acids and Bases:
In the laboratory, dilute solutions are often made from concentrated solutions of both strong
acids and strong bases. List the formulas for the dilution of a concentrated acid and the dilution
of a concentrated base in the space below:
3) Calculate the pH if 5.00 mL of 0.250 M HClO4 is diluted to 50.0 mL.
4) Calculate the pH when 1.00 mL of 0.175 M NaOH is diluted to 2.00 L.
Strong Acid and Strong Base Practice Problems
1) What is the pH of a 0.040 M solution of HClO4?
2) An aqueous solution of HNO3 has a pH of 2.34. What is the concentration of this acid?
3) What is the pH of a 0.063 M LiOH solution?
4) What is the pH of a 0.045 M Sr(OH)2 solution?
5) Calculate the concentration of an aqueous solution of NaOH that has a pH of 11.50.
6) Calculate the concentration of an aqueous solution of Ba(OH)2 that has a pH of 12.05.
7) Calculate the pH of a solution containing 0.525 g of HClO4 in 2000 mL of solution.
8) Calculate the pH if 5.00 mL of 1.00 M HCl is diluted to 0.50 L.
9) Calculate the pH when 1.565 g of KOH is dissolved in 500.0 mL of solution.
10) Calculate the pH when 10.0 mL of 0.015 M Ca(OH)2 is diluted to 500.0 mL.