SOLVED

41) Consider the following reaction, equilibrium concentrations, and equilibrium constant at a particular temperature. Determine the equilibrium concentration of CO2(g). NH2COONH4(s) ? 2 NH3(g) + CO2(g)Kc = 1.58 × 10-8 [NH3]eq = 2.7 × 10-3 M A) 0.053 M B) 4.3 × 10-11 M C) 2.2 × 10-3 M D) 5.9 × 10-6 M E) 0.022 M 42) For the isomerization reaction: butane ? isobutane Kp equals 25 at 500°C. If the initial pressures of butane and isobutane are 20. atm and 0.0 atm, respectively, what are the pressures of the two gases at equilibrium? A) P(butane) = 0.77 atm and P(isobutane) = 19.2 atm B) P(butane) = 0.80 atm and P(isobutane) = 20. atm C) P(butane) = 19.2 atm and P(isobutane) = 0.77 atm D) P(butane) = 20 atm and P(isobutane) = 0.80 atm 43) Cyclohexane, C6H12, undergoes a molecular rearrangement in the presence of AlCl3 to form methylcyclopentane, CH3C5H9, according to the equation: C6H12 ? CH3C5H9 If Kc = 0.143 at 25°C for this reaction, find the equilibrium concentrations of C6H12 and CH3C5H9 if the initial concentrations are 0.200 M and 0.050 M, respectively. A) [C6H12] = 0.019 M, [CH3C5H9] = 0.019 M B) [C6H12] = 0.181 M, [CH3C5H9] = 0.069 M C) [C6H12] = 0.219 M, [CH3C5H9] = 0.031 M D) [C6H12] = 0.224 M, [CH3C5H9] = 0.026 M 44) At a certain temperature the equilibrium constant, Kc, equals 0.11 for the reaction: 2 ICl(g) ? I2(g) + Cl2(g). What is the equilibrium concentration of ICl if 0.55 mol of I2 and 0.55 mol of Cl2 are initially mixed in a 2.0-L flask? A) 0.17 M B) 0.21 M C) 0.33 M D) 0.41 M 45) The equilibrium constant, Kp, equals 3.40 for the isomerization reaction: cis-2-butene ? trans-2-butene. If a flask initially contains 0.250 atm of cis-2-butene and 0.145 atm of trans-2-butene, what is the equilibrium pressure of each gas? A) P(cis-2-butene) = 0.0426 atm and P(trans-2-butene) = 0.145 atm B) P(cis-2-butene) = 0.0471 atm and P(trans-2-butene) = 0.160 atm C) P(cis-2-butene) = 0.0735 atm and P(trans-2-butene) = 0.250 atm D) P(cis-2-butene) = 0.0898 atm and P(trans-2-butene) = 0.305 atm 46) Phosphorus pentachloride decomposes to phosphorus trichloride at high temperatures according to the equation: PCl5(g) ? PCl3(g) + Cl2(g) At 250° 0.188 M PCl5 is added to the flask. If Kc = 1.80, what are the equilibrium concentrations of each gas? A) [PCl5] = 0.0164 M, [PCl3] = 0.172 M, and [Cl2] = 0.172 M B) [PCl5] = 0.0940 M, [PCl3] = 0.411 M, and [Cl2] = 0.411 M C) [PCl5] = 1.80 M, [PCl3] = 1.80 M, and [Cl2] = 1.80 M D) [PCl5] = 4.13 M, [PCl3] = 3.94 M, and [Cl2] = 3.94 M 47) Kc is 1.67 × 1020 at 25°C for the formation of iron(III) oxalate complex ion: Fe3+(aq) + 3 C2O42-(aq) ? [Fe(C2O4)3]3-(aq). If 0.0800 M Fe3+ is initially mixed with 1.00 M oxalate ion, what is the concentration of Fe3+ ion at equilibrium? A) 1.09 × 10-21 M B) 0.0100 M C) 2.09 × 1019 M D) 1.97 × 1021 M 48) Dinitrogen tetroxide partially decomposes according to the following equilibrium: N2O4(g) → 2NO2(g) A 1.000-L flask is charged with 8.00 × 10-3 mol of N2O4. At equilibrium, 5.04 × 10-3 mol of N2O4 remains. Keq