The concentration of hydronium ions and hydroxide ions can

Last updated: 5/5/2023

The concentration of hydronium ions and hydroxide ions can vary widely in a solution easily from 1 M to 1 x 10 14 M This variation is too wide to fit on an analog readout In order to make this into a smaller scale suitable for an analog readout the log to the base 10 was used so that the read out is focused on powers of 10 Note that the log 1 0 and the log of 1 x 10 14 14 It was then decided that the numbers should be positive so the sign was changed The way to measure concentrations of both H and OH was thus defined as log This was then referred to as p Thus pH log H pOH log OH and pK log Kegl You need to figure out how to do this mathematical manipulation on your calculator The acid base reaction in pure water is H O H O H 0 OH and it was found that in pure water under standard conditions the H30 OH 1 x 107 M Neutral pH is defined as having a H or H30 of 1 x 107 M The pH of a neutral solution is thus pH log 1 x 107 The pOH of a neutral solution is thus pOH log 1 x 107 a 7 b 6 C 8 27