Moles to Moles Stoichiometry Calculation Notes

Moles to Moles Stoichiometry Calculation Notes CP Chemistry

Stoichiometry • the study of quantitative relationships between amounts of reactants used and the products formed in a chemical reaction • shows the conservation of matter • mass of products = mass of reactants • requires balanced equations!!!

Mole Ratios • ratio of numbers between the numbers of moles of any two substances in a balanced chemical equation • used in stoichiometric calculations • example: 2 Al + 3 Br2 2 AlBr3 • ratio of Al:Br2 is 2:3 • ratio of Al:AlBr3 is 2:2 (or 1:1) • ratio of Br2:AlBr3 is 3:2

Mole to Mole Calculations • problem gives you moles of reactant or product and asks for moles of another reactant or product in the chemical equation

Steps to Solving Mole to Mole Problems • Balance chemical equation • Place number of moles given above compound in equation • Place an x above the compound for which you are calculating the number of moles • Pull down the ratios from the equation • Cross multiply to solve for x

Example 1 How many moles of potassium needs to react with water to produce 3 moles of H2 gas? K + H20  KOH + H2

Example 2 How many moles of water can be produced with 6 moles of hydrogen? H2 + O2 H2O

Example 3 How many moles of oxygen would be required to fully react with 8 moles of hydrogen? H2 + O2 H2O

Example 4 How many moles of water can be produced with 4 moles of oxygen? H2 + O2 H2O

Example 5 How many moles of hydrogen would be required to produce 10 moles of water? H2 + O2 H2O

Example 6 How many moles of oxygen would be needed to produce 20 moles of water? H2 + O2 H2O

Moles to Moles Stoichiometry Calculation Notes