1 / 18

Acids and Bases Notes

Acids and Bases Notes. Spring 2011. What is an acid or base?. A solution! Acid Solute: hydrogen ions (H + ) Base Solute: hydroxide ions ( - OH) Solvent: water. The pH scale . used to measure hydrogen ions (H + ) pH = “power of hydrogen” Litmus Test: pH < 7 is an ACID

satin
Télécharger la présentation

Acids and Bases Notes

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. Acids and Bases Notes Spring 2011

  2. What is an acid or base? • A solution! • Acid Solute: hydrogen ions (H+) • Base Solute: hydroxide ions (-OH) • Solvent: water

  3. The pH scale • used to measure hydrogen ions (H+) • pH = “power of hydrogen” • Litmus Test: • pH < 7 is an ACID • 7 is NEUTRAL (6.5 - 7.5) • pH > 7 is a BASE LITMUS PAPER

  4. Properties of acids • Have hydrogen ions (H+) • Have a sour or tangy taste • Acids are electrolytes: they have dissolved ions that conduct electricity • Turn litmus paper red • Ex: fruits, coffee, vinegar

  5. Properties of Bases • Have hydroxide (OH-) ions • Have a bitter taste • Are electrolytes • Turn litmus paper blue • Ex: shampoo, detergent, antacids

  6. Strong vs. Weak • A strong solution is (lots of solute) is close to the edge of the pH scale • Strong = more dangerous • Strong Acids = pH 0 - 1 • Strong Bases = pH 13 - 14

  7. Indicators • Dyes that turns colors based on pH • weak acids or weak bases • Universal indicator is a mix of several

  8. Litmus Paper • Red = acid • Blue = base

  9. Phenolphthalein • Clear in acids • Pink > pH 8

  10. Universal Indicator • A mix of several indicators • Changes color at each pH

  11. Common Indicators

  12. ACID The pH scale • measure hydrogen ion (H+) content • pH = “power of hydrogen” • range from 0 to 14 • 0 = very acidic • 14 = very basic BASE

  13. ACID 14 13 12 11 10 9 8 7 6 5 4 3 2 1 0 The pOH scale • Power of –OH (hydroxide) • How basic something is depends on hydroxide ion (OH-) concentration • OPPOSITE OF pH! • 0 = very basic • 14 = very acidic BASE

  14. pH and pOH • equation for switching between pH and pOH scales: pH + pOH = 14

  15. Formulas pH= -log [H+] 10(-pH) = [H+] pOH= -log [OH-] 10(-pOH) = [OH-]

  16. What is neutralization? • double-replacement reaction between an acid and a base • products are water and a salt • Salts are ionic compounds: • cation from a base • anion from an acid

  17. General Equation: Acid + Base  Salt + H2O -or- HX + QOH QX + HOH acid base salt water

  18. Titration • Neutralization is done by titration • drop-by-drop mixing of acid and base until the solution is neutral (pH = 7)

More Related