Presentation on theme: "Ways to measure Acidity/Basicity What is pH? What is pOH?"— Presentation transcript:
1 Ways to measure Acidity/Basicity What is pH? What is pOH? pH and pOHWays to measure Acidity/BasicityWhat is pH?What is pOH?
2 What is pH? pH = potential Hydrogen The pH scale measures how acidic or basic a substance is, is logarithmicThe pH scale ranges from 0 to 14.A pH of 7 is neutral.A pH less than 7 is acidic, greater than 7 is basic.
5 Calculating [H+] values EXAMPLE: Find [H+] if pH = 8.5[H+] = 10-pH [H+] = [H+] = 3.2 x 10-9 M
6 Calculating pOH pOH = 14 – pH pOH = -log[OH-] EXAMPLE: What is the pOH of a solution that has a hydroxide ion concentration of 4.82 x 10-5 M ?pOH = - log [OH-]pOH = - log [4.82 x 10-5]pOH = 4.32
7 YOU TRY! pH = 4 7.1 = -log [H+] 10 – 7.1 = [H+] = 7.9 x 10-8 M Find the pH of the solution if [H+] = 1 x 10-4 MWhat is the hydrogen ion concentration if pH = 7.1?What is the pH if [OH-] = 4 x M?pH = 47.1 = -log [H+]10 – 7.1 = [H+] = 7.9 x 10-8 MpOH = -log [OH-]pOH = -log [4 x ] =