pH

noun \ ˈpē-ˈāch \

Definition of pH

: a measure of acidity and alkalinity of a solution that is a number on a scale on which a value of 7 represents neutrality and lower numbers indicate increasing acidity and higher numbers increasing alkalinity and on which each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen-ion concentration or hydrogen-ion activity in gram equivalents per liter of the solution; also : the condition represented by a pH number

Origin and Etymology of ph

German, from Potenz power + H (symbol for hydrogen)


PH

abbreviation

Definition of PH

1 pinch hit
2 public health
3 Purple Heart

PH Defined for English Language Learners

pH

noun

Definition of pH for English Language Learners

  • : a number between 0 and 14 that indicates if a chemical is an acid or a base


PH Defined for Kids

pH

noun \ ˈpē-ˈāch \

Definition of pH for Students

: a measure of the acidity or alkalinity of a substance
  • Lemon juice has a pH of about 2.5.
  • Water has a pH of 7.

Medical Dictionary

ph

abbreviation

medical Definition of ph

1 pharmacopoeia
2 phosphor
3 phot

pH

noun \ (ˈ)pē-ˈāch \

medical Definition of pH

: a measure of acidity and alkalinity of a solution that is a number on a scale on which a value of 7 represents neutrality and lower numbers indicate increasing acidity and higher numbers increasing alkalinity and on which each unit of change represents a tenfold change in acidity or alkalinity and that is the negative logarithm of the effective hydrogen-ion concentration or hydrogen-ion activity in gram equivalents per liter of the solution
  • instead of saying that the concentration of hydrogen ion in pure water is 1.00 x 10−7, it is customary to say that the pH of pure water is 7
  • —Linus Pauling
; also : the condition represented by such a number — compare pk

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