Stoichiometry

Calculation of relative masses of reactants and products in chemical reactions

Stoichiometry is the relationships between the quantities of reactants and products before, during and after chemical reactions. Stoichiometry is based on the law of conservation of mass; the total mass of reactants must equal the total mass of products, so the relationship between reactants and products must form a ratio of positive integers. This means that if the amounts of the separate reactants are known, then the amount of the product can be calculated.

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