What does "equivalence" mean?

Equivalence: Equal power or force; equivalent amount.

Additional senses

  1. 2.(Chem.) (a) The quantity of the combining power of an atom, expressed in hydrogen units; the number of hydrogen atoms can combine with, or be exchanged for; valency. See Valence. (b) The degree of combining power as determined by relative weight. See Equivalent, n., 2. [R.]
  2. 3.To be equivalent or equal to; to counterbalance. [R.] Sir T. Browne.

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