Problem 13107 Chapter Problem 18 of Constants Periodic Tabl

Problem 13.107: Chapter Problem 18 of Constants | Periodic Table Part A Consider the reaction C (s) + CO2 (g) 2CO(g) What is the equilibrium concentration of CO2? When 1.46 mol of CO2 and an excess of solid carbon are heated in a 19.4 L container at 1100K the equilibrium concentration of CO is 7.01x10-2 M Submit Previous Answers Request Answer Incorrect, Try Again: 2 attempts remaining Part B What is the value of the equilibrium constant Kc at 1100 K? Submit Request Answer

Solution

Ans. Part A: Given-

            Initial moles of CO₂ = 1.46 mol

            Reaction volume = 19.4 L

            Equilibrium [CO] = 7.01 x 10^-2 M = 0.0701 M

Now,

            Initial [CO₂] = Moles of CO₂ / Reaction volume in liters

= 1.46 mol / 19.4 L

= 0.07526 M

# According to the stoichiometry of balanced reaction, 1 mol CO₂ forms 2 mol CO.

So,

[CO₂] consumed = ½ x [CO] formed = ½ x 0.0701 M = 0.03505 M

# Equilibrium [CO₂] = Initial [CO₂] – [CO₂] consumed

= 0.07526 M - 0.03505 M

= 0.04021 M

# Part B: Equilibrium constant, Kc = [CO]² / [CO₂]         - all [Conc.] at equilibrium

            Or, Kc = (0.0701)² / 0.04021 = 0.122

Hence, Kc = 1.22 x 10^-1