key term - Stoichiometric Calculations

Definition

Stoichiometric calculations are the mathematical procedures used to determine the quantitative relationships between the reactants and products involved in a chemical reaction. They allow for the prediction of the amounts of substances that will be produced or consumed during a reaction based on the balanced chemical equation.

5 Must Know Facts For Your Next Test

1. Stoichiometric calculations are based on the balanced chemical equation, which shows the mole ratios between the reactants and products.
2. The mole is the fundamental unit used in stoichiometric calculations, as it allows for the conversion between mass, volume, and number of particles.
3. The limiting reactant determines the maximum amount of products that can be formed in a chemical reaction, as it is the reactant that is completely consumed.
4. Excess reactants remain after a reaction has gone to completion and do not contribute to the formation of products.
5. Stoichiometric calculations are essential for predicting the yields of chemical reactions and ensuring the proper amounts of reactants are used.

Review Questions

• Explain how the balanced chemical equation is used in stoichiometric calculations.
  • The balanced chemical equation provides the stoichiometric coefficients, which represent the mole ratios between the reactants and products. These coefficients are used to determine the amounts of substances that will be consumed or produced during the reaction. By using the balanced equation, stoichiometric calculations allow for the prediction of the quantities of reactants and products based on the given information, such as the amount of a reactant or the desired product yield.
• Describe the role of the limiting reactant in stoichiometric calculations.
  • The limiting reactant is the reactant that is completely consumed in a chemical reaction, and it determines the maximum amount of products that can be formed. Identifying the limiting reactant is crucial in stoichiometric calculations, as it allows for the determination of the theoretical yield of the reaction. Stoichiometric calculations involve determining the limiting reactant based on the given amounts of reactants and using the balanced equation to calculate the corresponding product yield.
• Analyze how the presence of excess reactants affects the stoichiometric calculations and the overall reaction.
  • The presence of excess reactants in a chemical reaction does not contribute to the formation of products once the limiting reactant has been consumed. Stoichiometric calculations must account for the excess reactants, as they do not participate in the reaction but may need to be considered for practical purposes, such as ensuring the complete consumption of the limiting reactant or providing a buffer to drive the reaction to completion. Understanding the role of excess reactants is essential in stoichiometric calculations, as it allows for the optimization of reactant quantities and the prediction of the final composition of the reaction mixture.

Related terms

Mole:

The mole is the SI unit for amount of substance, defined as the number of particles (atoms, molecules, or ions) in a substance. It is used to quantify the amounts of reactants and products in a chemical reaction.

Limiting Reactant:

The limiting reactant is the reactant that is completely consumed in a chemical reaction, thereby determining the maximum amount of products that can be formed.

Excess Reactant:

The excess reactant is the reactant that remains after a chemical reaction has gone to completion, as it was present in an amount greater than what was required by the limiting reactant.