This preview shows pages 1–2. Sign up to view the full content.
This preview has intentionally blurred sections. Sign up to view the full version.View Full Document
Unformatted text preview: Aim: How are pH and pOH calculated? QQ: Which would have a lower pH, 1.0 M HCl or 1.0 M CH 3 COOH? Explain your answer. Do Now: What is the pH actually measuring? pH is a measurement of the concentration of H + ions (H 3 O + ions) in an aqueous solution acids: pH < 7 bases: pH > 7 pH = -log [H + ] Every 1 unit change in pH is equal to a 10x concentration change of H 3 O + ions. How much more concentrated is a solution with a pH of 3 than a pH of 6? 10 x 10 x 10 = 1000x more concentrated! What is the pH of a 0.05 M solution of HClO 4 ? HClO 4 (aq) H + (aq) + ClO 4- (aq) 0.05 M 0.05 M pH = - log [H+] pH = -log [0.05 M] pH = 1.3 Practice: Find the pH (assume complete dissociation). 1. 1.0 M HNO 2 2. 0.05 M H 3 PO 4 3. 3.6 x 10-4 M H 2 SO 3 4. 5.2 x 10-8 M HCl Pure water will dissociate to an extent H 2 O (l) + H 2 O (l) H 3 O + (aq) + OH- (aq) K w = [H 3 O + ] [OH- ] = 10-14 [H 3 O + ] = 10-7 M For extremely dilute solutions, the ions from water must be taken into account...
View Full Document
- Spring '11