In short, the solvent that can distinguish the acidity and alkalinity of two substances is called distinguishing solvent, otherwise it is called flattening solvent. The sodium hydroxide and potassium hydroxide mentioned in the title will be completely ionized when they are dissolved in water at the same time, which means that they are leveled by the solvent of water and show the same alkalinity. If ethanol or liquid ammonia is used as solvent, the alkalinity of the two can be distinguished.
In order to facilitate understanding, you can think that the strength of acidity and alkalinity here refers to the ability to give H + and oh -, but there is an upper limit to the ability of water to accept these two ions. A fat man of 180 kg and 200 kg can't compare who is heavier when standing on a scale with an energy of only 150 kg.
The alkalinity of alkali is different from that of solution. It should be the alkalinity of alkali. The alkalinity of alkali is related to the ionization degree of alkali. For two fully ionized strong bases, sodium hydroxide and potassium hydroxide, it is judged by the metal activity. From this point of view, potassium hydroxide is more alkaline than sodium hydroxide. The alkalinity of the solution is determined by the concentration of hydroxyl ion. The greater the concentration of hydroxyl ion, the stronger the alkalinity. The alkalinity of sodium hydroxide solution with the same molar concentration is the same as that of potassium hydroxide solution.
Difference between potassium hydroxide and sodium hydroxide
Potassium hydroxide is electrolyzed with potassium chloride aqueous solution, while sodium hydroxide is electrolyzed with sodium chloride aqueous solution. They are only different in raw materials (one is KCl and the other is NaCl) and products (one is KOH and the other is NaOH). The same thing is that they all go through brine refining, electrolysis and other processes, and the structure of the electrolytic cell is basically the same. Of course, many details must be different.
The molar mass of potassium hydroxide is greater than that of sodium hydroxide;
When the amount and concentration of the two substances are the same, the alkalinity of the solution is the same;
When the mass fraction of both solutions is the same, the alkalinity of sodium hydroxide solution is greater than that of potassium hydroxide;
The price of potassium hydroxide is higher than that of sodium hydroxide, but when configuring the same alkaline solution, the quality of potassium hydroxide is higher.