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Stoichiometric Equivalence

For two irreversible reactions, A and B, to be considered stoichiometrically equivalent, the following must be true:

  • The set of reactants for A and B must be identical.
  • The set of products for A and B must be identical.
  • The stoichiometric coefficients of A must be proportional to the corresponding coefficients in B.

For example, the irreversible reactions

2 H2 + O2 → 2 H2O and H2 + ½ O2 → H2O

are stoichiometrically equivalent. For two reversible reactions, A and B, to be considered stoichiometrically equivalent, the following must be true:

  • The set of reactants for A must be identical to either the set of reactants or products for B, and their stiochiometric coefficients must be proportional.
  • The set of products for A must be identical to either the set of reactants or products for B, and their stiochiometric coefficients must be proportional.

For example, the reversible reactions

2 NaCl + CaCO3 ↔ Na2CO3 + CaCl2 and ½ Na2CO3 + ½ CaCl2 ↔ NaCl + ½ CaCO3

are stoichiometrically equivalent.