1 / 12

Understanding pH, pOH, and Water Ionization Basics

This guide explains the fundamentals of pH and pOH, including their relationship with ion concentration in water. It covers the equations governing water's equilibrium with its ions (H2O ↔ H+ + OH-) and introduces the ion product constant (Kw = 1.0 x 10^-14 at 25°C). The tutorial explains acid and base definitions, provides examples of calculating pH and pOH from hydrogen and hydroxide ion concentrations, and discusses strong acids and bases. Learn how to use indicators for estimating pH and the significance of pH in various solutions.

borna
Télécharger la présentation

Understanding pH, pOH, and Water Ionization Basics

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. pH

  2. Water • Water is in equilibrium with its ions H2O(l)  H+(aq) + OH-(aq) Kw = [H+][OH-] • Kw = 1.0 x 10-14 at 25°C • In neutral solutions [H+]=[OH-]= 1x10-7 • If [H+]>[OH-], solution is acidic • If [H+]<[OH-], solution is basic

  3. Example • Find the [H+] if a) [OH-]= .010M b) [OH-]= 2.0 x 10-9 M

  4. pH • Very small numbers can be conveniently expressed on a log scale • pH = -log [H+] • pH = 7, neutral • pH < 7, acidic • pH > 7, basic

  5. Example • Calculate the pH of lemon juice with an [H+]= 3.8 x 10-4M • Calculate the pH of window cleaner with an [H+]= 5.3 x 10-9M • What is the [H+] of apple juice with a pH of 3.76.

  6. pOH • pOH = -log [OH-] • pOH = 7, neutral • pOH < 7, basic • pOH > 7, acidic • pH + pOH = 14.00

  7. Indicators • Used to estimate pH • Colored substance that exists in either acid or base form • Acid and base form are different colors • By knowing the pH where it changes color, we can determine its relative pH

  8. Strong Acids and Bases • Strong acids and bases ionize completely in solution • Strong acids: HCl, HBr, HI, HNO3, HClO4, H2SO4 (only the 1st H) • Strong bases: hydroxides of group I and II, except Be

  9. .10M HNO3 .10M H+ • .75M H2SO4  .75M H+ • .50M NaOH  .50M OH- • .75M Ca(OH)2  1.5M OH-

  10. Example • What is the pH of a solution of a) .010M HCl b) .010M Ca(OH)2

More Related