AP Ch 19 Electrochemistry

AP Ch 19 - Electrochemistry Chapter 19 Electron transfer reactions are oxidationreduction or redox reactions Results in the generation of an

Info iconThis preview shows pages 1–8. Sign up to view the full content.

View Full Document Right Arrow Icon
Electrochemistry Chapter 19
Background image of page 1

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Electron Transfer Reactions Electron Transfer Reactions Electron transfer reactions are oxidation- reduction or redox reactions. Results in the generation of an electric current (electricity) or be caused by imposing an electric current. Therefore, this field of chemistry is often called ELECTROCHEMISTRY.
Background image of page 2
2Mg ( s ) + O 2 ( g ) 2MgO ( s ) 2Mg 2Mg 2+ + 4e - O 2 + 4e - 2O 2- Oxidation half-reaction (lose e - ) Reduction half-reaction (gain e - ) 19.1 Electrochemical processes are oxidation-reduction reactions in which: the energy released by a spontaneous reaction is converted to electricity or electrical energy is used to cause a nonspontaneous reaction to occur 0 0 2+ 2-
Background image of page 3

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Terminology for Redox Reactions Terminology for Redox Reactions OXIDATION OXIDATION —loss of electron(s) by a species; —loss of electron(s) by a species; increase in oxidation number; increase in oxygen. increase in oxidation number; increase in oxygen. REDUCTION REDUCTION —gain of electron(s); decrease in —gain of electron(s); decrease in oxidation number; decrease in oxygen; increase oxidation number; decrease in oxygen; increase in hydrogen. in hydrogen. OXIDIZING AGENT OXIDIZING AGENT —electron acceptor; species is —electron acceptor; species is reduced. (an agent facilitates something; ex. reduced. (an agent facilitates something; ex. Travel agents don’t travel, they facilitate travel) Travel agents don’t travel, they facilitate travel) REDUCING AGENT REDUCING AGENT —electron donor; species is —electron donor; species is oxidized. oxidized.
Background image of page 4
You can’t have one… without the other! Reduction (gaining electrons) can’t happen without an oxidation to provide the electrons. You can’t have 2 oxidations or 2 reductions in the same equation. Reduction has to occur at the cost of oxidation LEO LEO the lion says the lion says GER GER ! ! o o s s e e l l e e c c t t r r o o n n s s x x i i d d a a t t i i o o n n a a i i n n l l e e c c t t r r o o n n s s e e d d u u c c t t i i o o n n GER! GER!
Background image of page 5

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Another way to remember OIL RIG x x i i d d a a t t i i o o n n s s o o s s e e e e d d u u c c t t i i o o n n s s a a i i n n
Background image of page 6
The charge the atom would have in a molecule (or an ionic compound) if electrons were completely transferred. 1. Free elements (uncombined state) have an oxidation number of zero. Na, Be, K, Pb, H 2 , O 2 , P 4 = 0 1. In monatomic ions, the oxidation number is equal to the charge on the ion. Li + , Li = +1 ; Fe 3+ , Fe = +3 ; O 2- , O = -2 1. The oxidation number of oxygen is usually –2 . In H 2 O 2 and O 2 2- it is –1 . 4.4
Background image of page 7

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
Image of page 8
This is the end of the preview. Sign up to access the rest of the document.

This note was uploaded on 05/25/2010 for the course CHEM 101 taught by Professor Fricke during the Spring '10 term at Canisius College.

Page1 / 38

AP Ch 19 - Electrochemistry Chapter 19 Electron transfer reactions are oxidationreduction or redox reactions Results in the generation of an

This preview shows document pages 1 - 8. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online