Chapter 4: Stoichiometry Section 4.2: Fundamentals of Stoichiometry Monday, September 15, 2014 2:32 PM Stoichiometry - study of relationships between quantities of reactants and products in chem reactions ? Obtaining Ratios from Balanced Equations ? -from the coefficients in the equation, all atoms are in ratios with one another Equation: CH4 + 2O2 = CO2 + 2H2O Ex: 1 mol CH4 : 2 mol O2 AND 1 mol CH4 : 1 mol CO2 **these are called "mole ratios" -frequently written as fractions -"molar mass ratios" relate molecular mass and molar mass ? ? This is a typical approach to solving reaction stoichiometry! ? Keep in mind the units for your final answer (in this case, grams of water) -also, use unit cancellation ? ?