And at 25 degrees Celsius, this equals 10 times ten to negative 14. Now, this process is called the autoimilization reaction. And if you want to learn more about this reaction, check out the link below. Now, in the same way that we talk about ionization constants of water, we can also talk about ionization constants of acids. Except now they're not Kw, they're ka, where A is for our acid. So let's suppose we have a hypothetical acid Ha reacting with a water molecule in a liquid state.