Ask Question
21 September, 07:58

CaCO3 (s) ⇄ CaO (s) + CO2 (g) 0.100 mol of CaCO3 and 0.100 mol CaO are placed in an 10.0 L evacuated container and heated to 385 K. When equilibrium is reached the pressure of CO2 is 0.220 atm. 0.270 atm of CO2 is added, while keeping the temperature constant and the system is allowed to reach again equilibrium. What will be the final mass of CaCO3? 15.01 g

+1
Answers (1)
  1. 21 September, 08:12
    0
    11.58 g

    Explanation:

    The equilibrium constant based on pressure (Kp) only relates the gases, so, for the reaction given, only the pressure of CO₂ will be considered. The equation is already balanced, so

    Kp = pCO₂

    Kp = 0.220

    So, if 0.270 atm is added, the equilibrium will shift to form the reactant, and Kp will remain the same (0.220), so the gas added will form CaCO₃. The number of moles of CO₂ can be calculated by the equation of ideal gas:

    PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the constant of the gases (R = 0.082 atm. L/mol. K), and is the temperature.

    First, let's calculated how much moles of CO₂ were formed in the equilibrium:

    0.220x10 = nx0.082x385

    31.57n = 2.20

    n = 0.0697 mol

    The stoichiometry is 1 mol of CaCO₃ for 1 mol of CO₂, so it was consumed 0.0697 mol of CaCO₃, and in the equilibrium, the number of moles of it is 0.100 - 0.0697 = 0.0303 mol

    For the quantity added, the number of moles is:

    0.270x10 = nx0.082x385

    31.57n = 2.70

    n = 0.0855 mol

    This will form more 0.0855 mol of CaCO₃, so the final number of moles is:

    n = 0.0303 + 0.0855 = 0.1158 mol

    The molar masses are: Ca = 40 g/mol, C = 12 g/mol, O = 16 g/mol

    CaCO₃ = 40 + 12 + 3x16 = 100 g/mol

    The mass is the number of moles multiplied by the molar mass:

    m = 0.1158x100

    m = 11.58 g
Know the Answer?
Not Sure About the Answer?
Find an answer to your question 👍 “CaCO3 (s) ⇄ CaO (s) + CO2 (g) 0.100 mol of CaCO3 and 0.100 mol CaO are placed in an 10.0 L evacuated container and heated to 385 K. When ...” in 📗 Chemistry if the answers seem to be not correct or there’s no answer. Try a smart search to find answers to similar questions.
Search for Other Answers