Question
Question: How can I extract sodium and chloride from salt?...
How can I extract sodium and chloride from salt?
Solution
Electrolysis is the process by which we can obtain sodium and chlorine from either molten or aqueous solution of salt which is also calledNaCl. For the production of sodium, electrolysis is a major method along with also being used for producing other alkali metals and alkaline earth metals from their salts.
Complete answer:
In the molten state of salt, elements can be extracted by heating it above its melting point of1,474∘F (801∘C). To set up the electrolysis set up, we shall insert two inert electrodes in the moltenNaCl. Here we take molten sodium chloride so that the ions of sodium and chlorine move easily and thus they are able to move to respective electrodes. Electricity is made to pass through the molten salt and that’s when the ions start to move freely. Now we know that like repels like and this happens with the ionic charge thus the negative electrode which is called cathode attracts the positive ion which is the sodium ion. Similarly, the positive electrode which is called the anode attracts the negative ions which is the chloride ion.
The diatomic molecule of chlorine is immediately formed as the atoms of chlorine combine with each other. The result is thus that the salt gets broken down into elements by electricity.
The reactions which take place at the electrodes are as follows:
oxidation (anode): $$$$$$2C{l^ - }(l) \to C{l_2}(g) + 2{e^ - }reduction(cathode):N{a^ + }(l) + {e^ - } \to Na(l)Overallreaction:2N{a^ + }(l) + 2C{l^ - }(l) \to 2Na(l) + C{l_2}(g)$$
Note: The equipment used for this process of electrolysis to occur is called Down’s cell. We obtain the liquid sodium metal on the cathode and there is the obtaining of chlorine in the form of gas as the chlorine ions are oxidised to chlorine gas at cathode. Chlorine is used in various areas such as it is used in bleaching.