Principle of electrolytic water: When a direct current is passed through certain aqueous solutions of electrolytes, the substances broken down have nothing to do with the original electrolyte. What is broken down is water as the solvent, and the original electrolyte remains in the water. For example, sulfuric acid, sodium hydroxide, potassium hydroxide, etc. all belong to this type of electrolytes.
In water electrolysis, because the ionization degree of pure water is very low and its conductivity is low, it is a typical weak electrolyte . Therefore, it is necessary to add the aforementioned electrolyte to increase the conductivity of water. The solution so that water can be electrolyzed gently. Become hydrogen and oxygen.
Electrolyzed water generally refers to the product generated after the electrolysis of water containing salt (such as sodium sulfate, table salt is not aauthorized and chlorine gas will be generated). The electrolyzed water itself is neutral and other ions can be added, or it can be separated by a semi-permeable membrane to generate water with two properties. One of them is alkaline ionized water and the other is acidic ionized water. Electrolyzed water using sodium chloride as the electrolyte contained in water will contain sodium hydroxide, hypochlorous acid and sodium hypochlorite after electrolysis (if pure water undergoes electrolysis, only the hydroxide ions, hydrogen gas, oxygen and hydrogen ions will be produced).
Under certain conditions, the acidic electrolyzed water produced after electrolysis can be used for sterilization. Oxygen generated at the electrode based on the principle of electrolysis will combine with chlorine to form an aqueous solution of hypochlorite or chlorite ions at a lower pH value (e.g. pH < 2.7) .
The eWater electrolysis experiment is an experiment to test the composition of water. According to the products produced during electrolysis, electrolysis can be divided into several types such as water type electrolysis, electrolyte type decomposition, hydrogenation type and alkali generation, oxygen generation and type of acid generation, etc. Water is made up of two elements: hydrogen and oxygen. The water is energized to generate hydrogen and oxygen. The positive electrode produces oxygen and the negative electrode produces hydrogen.
Put a large piece of sodium metal in the water. Under the action of hydrogen gas produced by the reaction of the part in contact with water, it can move irregularly on the water surface and emits a whistling sound, then the heat of reaction. It melts under the action of surface tension and gravity and transforms into a flattened and smooth spherical shape.
If the sodium block is large enough, the heat of reaction will continue to build up after fusion (because the bottom is in contact with water to generate hydrogen gas to form a air cushion, so the heat of reaction is difficult to be released by water cooling), and finally the hydrogen gas produced by the reaction with water will ignite, and the sodium itself will undergo a violent oxidation reaction with the oxygen in the air. At this time, a blue flame can be seen first and then. it turns into flames.
Detailed information:
Physical and chemical properties of metallic sodium
< p>1. The outermost shell of a sodium atom has only one electron, which can be easily lost.2. What is the reaction between sodium and oxygen?
3. In addition to combining directly with Cl2, sodium can also combine directly with de many other non-metals. combines with sulfur, it will explode.
4. It is a silvery-white colored soft metal that is very soft and can be easily cut with a knife. After cutting the outer skin, you can see that the sodium has a silvery-white metallic sheen. Sodium is heat and electricity good conductors. The density of sodium is 0.97 g/cm3, which is less than the density of water, 1.0 g/cm3. The melting point of sodium is 97.81℃ and the boiling point is 882.9℃.
5. The chemical properties of sodium are very active, so it cannot exist in a free state in nature. Therefore, sodium is usually stored in liquid paraffin in the laboratory.
Reference documents:
Baidu-Metal Sodium Encyclopedia