Stoichiometry & Limiting Reactant

Front

What is stoichiometry?

Back

Stoichiometry is the branch of chemistry that deals with the calculation of reactants and products in chemical reactions based on the conservation of mass.

Front

What is a limiting reactant?

Back

A limiting reactant is the substance that is completely consumed in a chemical reaction, limiting the amount of product that can be formed.

Front

How do you determine the limiting reactant in a reaction?

Back

To determine the limiting reactant, calculate the moles of each reactant and compare the mole ratios required by the balanced equation.

Front

What is the mole ratio?

Back

The mole ratio is the ratio of moles of one substance to moles of another substance in a balanced chemical equation.

Front

Given the reaction 2H2 + O2 -> 2H2O, how many moles of H2O are produced from 3 moles of O2?

Back

6 moles of H2O.

Front

What is the purpose of stoichiometric calculations?

Back

Stoichiometric calculations are used to predict the amounts of products formed or reactants needed in a chemical reaction.

Front

What is the molar mass of oxygen (O2)?

Back

The molar mass of O2 is 32 grams per mole.

Front

In the reaction P4O10 + 6 H2O -> 4 H3PO4, what is the mole ratio of H2O to H3PO4?

Back

The mole ratio of H2O to H3PO4 is 6:4.

Front

What is the significance of the coefficients in a balanced chemical equation?

Back

The coefficients indicate the relative number of moles of each substance involved in the reaction.

Front

How can you predict the amount of product formed in a reaction?

Back

By using the mole ratio from the balanced equation and the amount of limiting reactant.