The two simplest sequences to work with are arithmetic and geometric sequences. An arithmetic sequence goes from one term to the next by always adding (or subtracting) the same value. For instance, 2, 5, 8, 11, 14,... is arithmetic, because each step adds three; and 7, 3, â1, â5,... is arithmetic, because each step subtracts 4.
Report Abuse. Yes pH is temperature dependent. So if you have water with a pH of 6.9 (very mildly acidic) at 12 C, and raise the temp up to about 22 C, the pH will reduce to about 6.7, which is more acidic. Jason, only pure water is neutral... most water you come across on a daily basis is not pure and doesn't have a pH of 7. derekbradley4000 Â· 8 years ago.
Hydronium is very acidic: at 25 Â°C, its pKa is â1.7. It is the most acidic species that can exist in water (assuming sufficient water for dissolution): any stronger acid will ionize and protonate a water molecule to form hydronium.