Learn about Senior Chemistry, Redox 6, in this comprehensive video by bannanaiscool.
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Male Speaker: All over Alberta you'll see signs like this one, and some of them will actually have warning cathodically protected cable below, what's that mean, that means then that there is a middle pipe under the ground that they are running current through to protect it from corrosion that's cathodic protection there is a lots of different ways to do that do too. How can you protect, iron pipe under the ground or metals any where, from this, this O2 and water half reaction, oxygen and water in the environment they loved to gain 4 electrons determine to hydroxide, and they will gain them from left over right, this is the way they are raised on the chart they will gain from iron and take and break iron, or magnesium, break it down, these are valuable metals and so we have to find a way to be able to prevent, this reaction from causing so much damage, or how do we do that, well we can paint the surface of the metal that will keep this away. We can actually run an electrical current a longer piece of iron that's why the electrons to this state of the iron. So we can protect the iron from this cathode because there we got reduction through cathodic protection but that neatest way in order to accomplish this is to take a piece of magnesium and just touch it on a rapid around the iron what the magnesium does because it's a stronger oxidizing agent this is arrangement of them on the chart, that magnesium will actually protect the iron and donate its electrons first. So will zinc and therefore that's what we quote nails, with zinc its called galvanizing, because then it protects the iron which does the major part of holding the fence together and the zinc rusts first, cathodic protection it is so cool.