transcription, транскрипция: [ pi: eɪtʃ ]
The pH of a solution indicates how acid or alkaline the solution is. A pH of less than 7 indicates that it is an acid, and a pH of more than 7 indicates that it is an alkali.
...the pH of sea water...
Skin is naturally slightly acidic and has a pH of 5.5...
N-UNCOUNT : also a N , oft N of n , N num