Survey
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
* Your assessment is very important for improving the workof artificial intelligence, which forms the content of this project
Chemistry Chapter 19 D Defined: branch of chemistry that deals with electricity-related redox reactions Electrochemical cell: ◦ System of electrodes and electrolytes that produces an electric current ◦ System of electrodes and electrolytes that causes chemical change as current moves Electrode Half-cell Cathode Anode ◦ Conductor used to make electrical contact with a nonmetallic part of a circuit ◦ Single electrode immersed in a solution of its ions ◦ Electrode where reduction takes place ◦ Electrode where oxidation takes place Electrochemical cell in which redox takes place naturally and produces a current ◦ Cations are reduced at the cathode ◦ Anions are oxidized at the anode ◦ Electrons given up at anode are passed on external connecting wire to cathode (current flows) Zinc-carbon dry cell (dry cell battery) ◦ Zinc can is anode Zn(s) -> Zn2+(aq) + 2e◦ Carbon rod is cathode 2NH4+(aq) + 2MnO2(s) + 2e- -> Mn2O3(s) + H2O(l) + 2NH3(aq) Alkaline Battery ◦ Smaller, less corroding effect on container ◦ Anode is zinc Zn(s) + 2OH-(aq) Zn(OH)2(s) + 2e◦ Cathode is carbon or carbon alloy 2MnO2(s) + H2O(l) + 2e- Mn2O3(s) + 2OH-(aq) Mercury Battery ◦ Have large storage capacity, long shelf life, stable voltage output ◦ Contain toxic materials ◦ Anode is zinc Zn(s) + 2OH-(aq) -> Zn(OH)2(s) + 2e◦ Cathode is HgO/graphite alloy HgO(s) + H2O(l) + 2e- Hg(l) + 2OH-(aq) Read pages 606-610