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1. Maths
a. having a particular property in common; equal
b. (of two equations or inequalities) having the same set of solutions
c. (of two sets) having the same cardinal number
2. Maths Logic (of two propositions) having an equivalence between them



The equivalent of an element is the weight, expressed in carbon mass units, that will combine with or replace one atomic weight of hydrogen or one-half atomic weight of oxygen.

The equivalent of an acid is equal to the acid’s molecular weight divided by its alkalinity (number of hydrogen ions).

The equivalent of a base is equal to the base’s molecular weight divided by its acidity (number of hydroxyl groups).

The equivalent of a salt is equal to the molecular weight of the salt divided by the sum of the charges of the cations or anions forming the salt.

In oxidation-reduction reactions, the equivalent of an oxidizing agent is equal to the quotient obtained as a result of dividing the agent’s molecular weight by the number of electrons obtained by the atom or atoms of the reduced element. The equivalent may vary, depending on the number of electrons accepted by the oxidizing agent.

The concept of equivalent is widely used in the stoichiometric calculations of chemical reactions.


References in periodicals archive ?
Furthermore, the functionality and equivalent weight required for most coatings polyols is not inherent in the rPET as supplied, so hydroxyl end groups need to be generated.
Depending on the polyol composition, the crosslink system used, the functionality, and the equivalent weight, a wide spectrum of combined properties are available.
The polymer composition is expressed in terms of the equivalent weight defined as the weight in grams of polymer containing one equivalent of acid or, alternatively, the comonomer molecular weight plus 100n.
In all three cases, very good to excellent correlations were found between continuous real-time DES output and the values of characteristic QC parameters (viscosity, acid number, epoxy equivalent weight, % NCO, ATR-FTIR peak heights for reactants and products, and GPC data) determined by off-line analysis of samples taken periodically during the reactions.
This increases take-off power to 2,150 shaft horse power from 2,000 shp, creating better airfield and climb performance at equivalent weights.