1 / 22

National 5 Supported Study

National 5 Supported Study. Acids and Bases. Mandatory Areas. Acids and bases Dissociation of water into hydrogen and hydroxide ions. pH is related to the concentration of hydrogen and hydroxide ions in pure water, acids and alkalis. Neutralisation Titrations. Water.

karenperez
Download Presentation

National 5 Supported Study

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. National 5 Supported Study Acids and Bases

  2. Mandatory Areas • Acids and bases • Dissociation of water into hydrogen and hydroxide ions. • pH is related to the concentration of hydrogen and hydroxide ions in pure water, acids and alkalis. • Neutralisation • Titrations

  3. Water • Water contains hydrogen and hydroxide ions. • H2O(l) H+(aq) + OH-(aq) 99% 1% • Hence why water is covalent but conducts electricity • A small percentage of water actually exists as Hydrogen and Hydroxide Ions

  4. pH • In pure water • [H+] = [OH-] • The concentration of hydrogen ions equals the concentration of hydroxide ions • Hence why water has a pH of 7

  5. pH • In ACIDIC solutions • [H+] > [OH-] • The concentration of hydrogen ions is greater than the concentration of hydroxide ions

  6. Acids • pH less than 7 • Contain more Hydrogen ions (H+) than hydroxide ions (OH-) • When diluted • Concentration of H+ ions decreases • pH INCREASES towards 7

  7. pH • In ALKALINE solutions • [H+] < [OH-] • The concentration of hydroxide ions is greater than the concentration of hydrogen ions.

  8. Alkaline Solutions • pH greater than 7 • Contain more hydroxide ions (OH-) than Hydrogen ions (H+) • When diluted • Concentration of OH- ions decreases • pH DECREASES towards 7

  9. Neutralisation • A neutralisation reaction is where an acid is neutralised by a base resulting in a neutral solution. • A base is a substance which can neutralise an acid • Metal Oxides e.g. MgO CaO • Metal Carbonates e.g. CaCO3, BaCO3 • Metal Hydroxides e.g. NaOH, Mg(OH)2

  10. Formula of Acids – Learn

  11. KEY NEUTRALISATION REACTIONS Acid + Metal Salt + Water Hydroxide Acid + Metal Oxide Salt + Water • Acid + Metal Salt + Water + CO2 carbonate

  12. Naming Salts • Ending comes from the Acid • Hydrochloric = Chloride salt • Nitric = Nitrate Salt • Sulphuric = Sulphate Salt • Beginning comes from the Metal part of base

  13. Name that salt! • Lithium hydroxide + Hydrochloric acid • Calcium hydroxide + sulphuric acid • Potassium hydroxide + nitric acid • Ammonium hydroxide + hydrochloric acid • Sodium hydroxide + carbonic acid

  14. Answers! • Lithium chloride + water • Calcium sulphate + water • Potassium nitrate + water • Ammonium chloride + water • Sodium carbonate + water

  15. Titration Acid will be measured in burette Alkali in pipette (10cm3)

  16. RESULTS TABLE

  17. Titration Question • If 25cm3 of HCl is neutralised by 50cm3 NaOH (0.2mol/l), what is the concentration of the acid? HCl + NaOH NaCl + H2O

  18. Spectator Ions • They watch the reaction and do not take part • They are exactly the same on the reactant and product side. • Same state, same number, same charge

  19. 2010

  20. 2007

  21. 2006

  22. Precipitation Reactions • Precipitate = a solid • Precipitation reaction is when two solutions (aq) are reacted together and an insoluble product is formed – a solid (s) • Easily identified by state symbols • (aq) + (aq)  (s) + (aq)

More Related