Hello and welcome to another #steemitschool blog! Today we will be learning about the process of Electrolysis!
Let's get started...
What is 'Electrolysis'
Electro = electricity
Lysis = splitting
Electrolysis is a chemical process that 'splits' compounds into its original elements using electricity.
Key definitions for electrolysis
Electrolyte - An ionic compound that is either molten/dissolved and is able to conduct electricity.
Electrode - A metal rod that allows electrical current to pass through into/out of the electrolyte.
anode - The positive electrode.
cathode - The negative electrode.
Ions - Particles that carry either a positive or negative charge.
cations - ions that carry a positive charge and are attracted to the negative cathode.
anions - negatively charged ions that are attracted to the positive anode.
Electron - Tiny particle that has a negative charge found on the outside of an atom's nucleus.
How does electrolysis work?
The electric current is sent through the electrolyte.
The ions within it should move in the direction of the electrodes.
The positive ions (AKA cations) will move toward the negative electrode (AKA cathode) where electrons are gained- Positive charge reduced. (reduction)
The negative ions (AKA anions) will reach the positive electrode (AKA Anode) where electrons are lost - positive charge gained. (oxidation)
Through ions gaining/losing electrons, an uncharged element is produced as is taken out from the electrolyte.
Important rule for molten electrolysis ( process above)
Metal made at the cathode (negative electrode)
Non-metal made at anode (positive electrode)
e.g. Magnesium chloride...
Magnesium = formed at cathode
chloride = formed at anode
Why does an ionic compound have to be molten rather than a solid for electrolysis?
The ions within the electrolyte need to be free to move in order to transport electrical charge. If an ionic compound is in solid form, the ions will be in a fixed position where they are unable to move - this preventing the current from being carried.
Cool fact... metals can be extracted from their ores through electrolysis!
Usually, if a metal needs to be removed from it's ore, carbon can be used. For example, carbon can be used to reduce the amount of oxygen in Iron oxide to form Iron.
However... carbon can only be used to extract metals that are lower down in the reactivity series than itself.
So, 'what happens to the metals that are more reactive than carbon'? you're probably wondering. This is where electrolysis comes in to play!
The only down side to using electrolysis to extract metals is the expense and the significant amount of energy it requires.
Summary... here's a video.
(credit: Youtube: fuse/school)
Thanks for reading! The Information contained within this blog has been sourced from an AQA chemistry textbook and other online resources. I hope you learnt something new today!
Wishing you all a happy weekend and Easter.
Jonathan :)
