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