STOICHIOMETRY

What is stoichiometry? Stoichiometry is the quantitative study of reactants and products in a chemical reaction.

Mole Ratios The proportions of reactants and products (the recipe) is referred to as the MOLE RATIO. A mole ratio converts moles of one compound in a balanced chemical equation into moles of another compound.

Example Reaction between magnesium and oxygen to form magnesium oxide. 2 Mg(s) + O2(g) 2 MgO(s) Mole Ratios: 2 : 1 : 2

Practice Problems N2 + 3 H2 2 NH3 Write the mole ratios for N2 to H2 and NH3 to H2. Butane (C4H10) is a fuel used in BBQ lighters. Write out a balance reaction equation for the complete combustion of butane. A can of butane lighter fluid contains 1.20 moles of butane calculate the number of moles of carbon dioxide given off when this butane is burned.

Solving equivalent ratios, MEANS=EXTREMES Mole-Mole Problems Equation of reaction 2C4H10 + 13O2 8CO2 + 10H2O Mole ratio C4H10 CO2 2 : 8 [ from equation] 1.2 : X [ problem] 2 : 8 = 1.2 : X Solving equivalent ratios, MEANS=EXTREMES X = 4.8 mols of CO2 given off

Homework Read section7.1 Bottom half of handout from yesterday Page 319 #1-3 Questions on pg 320 if more practice needed