1 / 13

In the Laboratory

pH. In the Laboratory. Ionization of Water. Equllibrium Constant, K eq. Ion Product of Water, K W. pH. Acidity. Measuring pH. Indicater Dyes; Methyl Red, Phenol Red, etc. pH Paper (Litmus Paper) pH Meter. pH Meter. Voltmeter with electrode

Télécharger la présentation

In the Laboratory

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 In the Laboratory

  2. Ionization of Water

  3. Equllibrium Constant, Keq

  4. Ion Product of Water, KW

  5. pH

  6. Acidity

  7. Measuring pH • Indicater Dyes; Methyl Red, Phenol Red, etc. • pH Paper (Litmus Paper) • pH Meter

  8. pH Meter • Voltmeter with electrode • Measures electrical potential difference across electrode due to protons • 1 pH unit = 60 mV • pH also dependent on temperature

  9. pH Electrode • Filled with reference solution (4 M KCl, sat. AgCl) • Glass semi permable (protons cannot cross) • Glass protected by plastic sleeve • Some are sensitive to Tris buffer

  10. pH Standards • Color coded 4, 7, and 10 • Potassium Hydrogen Pthalate • Standardize everyday • Bracket pH range

  11. pH of Strong Acids • HCl <-> H+ +Cl- • Assume complete dissociation • 1 M HCl, pH = -log [H+] = -log 1 = ? • 0.5 M HCl, pH = -log 0.5 = ? • 6 M HCl, pH = -log 6 = ?

  12. pH of Strong Bases • NaOH <-> Na+ + OH- • Assume complete dissociation • pKW = pH + pOH = 14 • pH = 14 – (-log [OH-]) • 1 M NaOH, pH = 14 – (-log 1) = ? • 0.01 M NaOH, pH = 14 – (-log 0.01) = ? • 6 M NaOH, pH = 14 – (-log 6) = ?

  13. pH of a Weak Acid

More Related