1 / 8

Redox 3

Redox 3. The Activity Series. Identifying Redox Reactions. Oxidation and reduction occur together When an atom looses one or more electrons (Ox), another atom must gain them (red) Reducing agent – causes reduction to occur Looses one or more electrons Is oxidised

urbana
Télécharger la présentation

Redox 3

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. Redox 3 The Activity Series

  2. Identifying Redox Reactions • Oxidation and reduction occur together • When an atom looses one or more electrons (Ox), another atom must gain them (red) • Reducing agent – causes reduction to occur • Looses one or more electrons • Is oxidised • Oxidising number of atom increases • Metals act as reducing agents • Oxidising agent – causes oxidation to occur • Gains one or more electrons • Is reduced • Oxidation number of atom decreases • Reactive non-metals act as reducing agents

  3. P130 Group 1 metals give up only 1electron to leave M+ group 2 metals usu. give up 2 electrons to leave a dipositive ion (M2+). Transition metals – vary, we work out the oxidation of transition metals by considering the LIGANDS, e.g. Cl in TiCl4 is -1, so Ti must be Ti+4.

  4. Example • Identify the species oxidised, the species reduced, the oxidising agent and reducing agent in the following reaction: • Find the oxidation number of all species present • H • O • Sn Sn • Mn Mn The oxidation number of Mn changes from a +7 to +2, decrease in ox. no. Mn7+ is the species reduced, and MnO4- is the oxidising agent.

  5. Practice exam question • Identify the species oxidised, the species reduced, the oxidising agent and reducing agent in the following reaction • Step 1: determine the oxidation numbers of all species present • Step 2: identify the species which have a change in oxidation number • Step 3: based upon the change in oxidation number, identify the species oxidised, the species reduced and the oxidising and reducing agent.

  6. Additional Problems (p 152) • Where in the periodic table are the best reducing agents found? The best oxidising agents? • Where are the most easily reduced elements found? The most easily oxidised? • Does the substance gain or loose electrons in a redox reaction? • A) an oxidising agent • B) a reducing agent • C) A substance being oxidised • D) a substance undergoing reduction

  7. Assign oxidation numbers to each element: • NO2 SO3 • COCl2 MgH2 • KClO3 NO2- • V2O74- BrO- • Mn2O7 OsO4 • CH2O H2PtCl6

  8. Which is oxidised, which is reduced??

More Related