CHEM 135 1st Edition Lecture 15 Outline of Last Lecture I. Practice ProblemsII. Read section 13.7 and watch video posted on BBOutline of Current Lecture I. Chemical Equilibriuma. Introductionb. DefinitionII. Reversible reactions and Equilibrium Constanta. Definitionsb. Equationsc. ExamplesIII. Heterogeneous Equilibriuma. Definitionb. ExamplesCurrent LectureChemical EquilibriumN2 + 3H2 ⇌ 2NH3 This equation can go both ways and is reversible. The rates of the reaction are the same, meaning they are at equilibrium, no significant change inconcentrationDoes this mean the reaction stops?No, there is constant movement, even in equilibrium, in order to keep the reaction balanced.Reversible Reactions and Equilibrium ConstantsaA + bB ⇌ cC + dDThese notes represent a detailed interpretation of the professor’s lecture. GradeBuddy is best used as a supplement to your own notes, not as a substitute.- Rates of the forward and reverse reactions are equal at equilibrium.- Equilibrium does NOT mean the products are equalKeq=[ products ][reactants]Keq=[C]c[ D]d[ A ]a[B ]b- The constant within this equation is unitless.Ex. CH4 + 4Cl2 ⇌ CCl4 + 4HClCClHCl¿4¿[¿ ¿4 ]¿¿Keq=¿Ex. C3H8 + 5O2 ⇌ 3CO2 + 4H2OOH2¿¿¿4¿O2¿5CO2¿3¿¿Keq=¿- If Keq >> 1, it consists of more product than reactant (greater numerator)- If Keq << 1, it consist of more reactant than product (greater denominator)Heterogeneous Equilibrium- Reactants and products are in different phaseso 2CO2(g) ⇌ CO2(g) + C(s)o Equilibrium constant: COC O2¿2¿[¿¿2]¿KC=¿- Do not include: pure solids and pure liquids in an equilibrium constant- Changing the amount of solid does not change the concentration of gas Ex. Solve the following expressions and determine whether or not it favors the products or reactants. 1. SnO2(s) + 2CO(g) ⇌ Sn(s) + 2CO2(g) (CO2= 2M, CO=2M)CO¿¿ 2 ¿2¿¿Keq=¿This equation favors neither the reactant nor product2. NaCl(s) + H2SO4(l) ⇌ HCl(g) +NaHSO4(s)(HCl=3M)Keq=[HCl]=3This equation favors the product3. P4(s) + 6NO(g) ⇌ P4O6(s) + 3N2(g) (NO= 2M, N2=2)N2¿3¿NO¿6¿¿¿Keq=¿This reaction favors the
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