Electricity is conducted through salt water due to the movement of ions, specifically sodium (Na+) and chloride (Cl-) ions, which migrate towards the respective electrodes when an electric field is applied. The energy required to move these ions is significantly lower than that needed to transfer electrons between them, as they are stabilized in their ionic form by interactions with water. The polar nature of water prevents the ions from becoming neutral atoms, thereby maintaining their ionic state and facilitating current flow. The electric field from an external battery causes chloride ions to lose electrons at the anode, while sodium ions gain electrons at the cathode.
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sameeralord said:Ok so when I pass electricty through salt water the negative ions move from highly negative area to positive area causing a current? My question is why do the move? Let's say there was Sodium and Chloride ions in water. Can't the chloride ion give an electron to sodium and make the whole solution deionized, why do they choose to move instead?
Thank you
If that happens, it indicates a chemical reaction. For every chemical reaction to happen, it requires appropriate environment i.e. pressure, temperature and other parameters. Now water being a polar solvent doesn't provide chloride ions appropriate environment to transfer their excess electrons to sodium ions. Instead they remain ionized in a polar solvent like water as the water provides that kind of environment to stay them ionized. After being ionized the anion chloride ions are attracted to the anode connected to the +ve terminal of the battery and cation sodium ions are attracted to the cathode connected to the -ve terminal of the external battery. Then each of them take and leave electrons in the cathode and anode.
I have just one mini question left.The event of losing electrons in anode can be interpreted in terms of the electric field set up by the external battery. As the battery exerts an electric force on the negatively charged chloride ion, its excess electron located loosely in its out most shell is attracted by the electric force . The electric force F= qE accelerates the excess electron of chloride ion to the direction of +ve terminal. Hence, chloride ion leaves electrons in anode.