Can an aqueous solution conduct electricity forever? Ask Question. Asked 7 years, 10 months ago. Active 3 years, 6 months ago. Viewed 3k times. Improve this question. DanHickstein DanHickstein 2 2 silver badges 9 9 bronze badges.
How much of your argument applies if the current is AC not DC? I would expect that the usual 60 Hz AC current effectively acts like a DC current on the relevant timescales for the chemistry that takes place, but I am not sure about this.
It is a very very small current though. Add a comment. Active Oldest Votes. Hopefully someone will post a counter-example and make things more interesting : In the case of alternating current, it seems possible to plate material onto one electrode and remove it from the other. Improve this answer. The copper is plating onto one electrode and depleting it to the other electrode. Jaroslav Kotowski Jaroslav Kotowski 2, 1 1 gold badge 12 12 silver badges 23 23 bronze badges.
And how do they reverse to return ions to the solution? So, I don't understand how electrons would be drawn from or returned to an electrode. For DC, one electrode would be consumed and the reaction would stop. But, for AC, the electrodes would alternate depositing and removing materials and end up staying the same size. Show 2 more comments. Skylar Adams Skylar Adams 1 1 bronze badge. Water and electricity don't mix, right? Well actually, pure water is an excellent insulator and does not conduct electricity.
The thing is, you won't find any pure water in nature, so don't mix electricity and water. Our Water Science School page will give you all the details.
You're never too old to learn something new. All my life I've heard that water and electricity make a dangerous pair together. And pretty much all of the time that is true—mixing water and electricity, be it from a lightning bolt or electrical socket in the house, is a very dangerous thing to do. But what I learned from researching this topic was that pure water is actually an excellent insulator and does not conduct electricity.
Water that would be considered "pure" would be distilled water water condensed from steam and deionized water used in laboratories , although even water of this purity can contain ions. But in our real lives, we normally do not come across any pure water. If you read our article about water being the " universal solvent " you know that water can dissolve more things than just about any other liquid. Water is a most excellent solvent. It doesn't matter if the water comes out of your kitchen faucet, is in a swimming pool or dog dish, comes out of the ground or falls from the sky, the water will contain significant amounts of dissolved substances, minerals, and chemicals.
These things are the solutes dissolved in water. Don't worry, though—if you swallow a snowflake, it won't hurt you; it may even contain some nice minerals your body needs to stay healthy. Water stops being an excellent insulator once it starts dissolving substances around it. Salts , such as common table salt sodium chloride NaCl is the one we know best.
In chemical terms, salts are ionic compounds composed of cations positively charged ions and anions negatively charged ions. In solution, these ions essentially cancel each other out so that the solution is electrically neutral without a net charge.
Even a small amount of ions in a water solution makes it able to conduct electricity so definitely don't add salt to your "lightning-storm" bathwater. Standard electrode potentials table : This is the standard reduction potential for the reaction shown, measured in volts.
Positive potential is more favorable in this case. Historically, oxidation potentials were tabulated and used in calculations, but the current standard is to only record the reduction potential in tables. If a problem demands use of oxidation potential, it may be interpreted as the negative of the recorded reduction potential.
The production of this low-energy and stable electron configuration is clearly a favorable process. Recall that a more positive potential always means that that reaction will be favored; this will have consequences concerning redox reactions. Privacy Policy. Skip to main content. Aqueous Reactions. Search for:. Types of Aqueous Solutions Electrolyte and Nonelectrolyte Solutions Unlike nonelectrolytes, electrolytes contain dissolved ions that enable them to easily conduct electricity.
Learning Objectives Recognize the properties of an electrolyte solution. Key Takeaways Key Points Electrolytes are salts or molecules that ionize completely in solution. As a result, electrolyte solutions readily conduct electricity. Nonelectrolytes do not dissociate into ions in solution; nonelectrolyte solutions do not, therefore, conduct electricity. Key Terms nonelectrolyte : A substance that does not dissociate into ions when in solution.
Learning Objectives Explain why some molecules do not dissolve in water. Key Takeaways Key Points Water dissociates salts by separating the cations and anions and forming new interactions between the water and ions. Water dissolves many biomolecules, because they are polar and therefore hydrophilic. Key Terms dissociation : The process by which a compound or complex body breaks up into simpler constituents such as atoms or ions, usually reversibly.
Electrolytic Properties When electrodes are placed in an electrolyte solution and a voltage is applied, the electrolyte will conduct electricity. Learning Objectives Use a table of standard reduction potentials to determine which species in solution will be reduced or oxidized. Key Takeaways Key Points When an electrical current passes through a solution often of electrolytes , a cation or neutral molecule gets reduced at the cathode, and an anion or neutral molecule gets oxidized at the anode.
To determine which species in solution will be oxidized and which reduced, a table of standard reduction potentials can identify the most thermodynamically viable option. In practice, electrolysis of pure water can create hydrogen gas. Key Terms electrode : the terminal through which electric current passes between metallic and nonmetallic parts of an electric circuit; in electrolysis, the cathode and anode are placed in the solution separately.
Licenses and Attributions.
0コメント