Magnesia (MgO) is used for fire brick, crucibles, and furnace linings because of its high melting point. It is produced by decomposing magnesite (MgCO3) at around 1200 oC.
1. Calculate the equilibrium pressure of CO2(g) (in atmospheres) above MgCO3(s) at 298 K.
2. Calculate the equilibrium pressure of CO2(g) (in atmospheres) above MgCO3(s) at 1200 K.
Write the equation:
MgCO3 (s) <> CO2 (g) + MgO (s)
keq= [CO2]
now [CO2] is in units of moles/liter for the gas.
But moles/liter= Pressure/R*T
or Pressure= moles/liter *RT
Pressure= keq*RT
check my thinking
Your thinking is on the right track!
To calculate the equilibrium pressure of CO2 above MgCO3 at a given temperature, you can use the ideal gas law and the equilibrium constant expression.
1. To calculate the equilibrium pressure of CO2 at 298 K:
The ideal gas law is given by PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature in Kelvin.
The equilibrium constant expression for the reaction is K = [CO2], which means that K represents the concentration of CO2 at equilibrium.
Since CO2 is in the gas phase, we can express K as a pressure using the equation:
K = P_CO2 / (RT), where P_CO2 is the partial pressure of CO2.
Since you want to find the equilibrium pressure, we can rewrite the equation as:
P_CO2 = K * (RT)
Substituting the given values, we have:
K = [CO2] (but it's not given in the problem statement)
R = 0.0821 L·atm/mol·K (ideal gas constant)
T = 298 K (given temperature)
2. To calculate the equilibrium pressure of CO2 at 1200 K:
Using the same process as above, substitute the given values into the equation:
K = [CO2] (but it's not given in the problem statement)
R = 0.0821 L·atm/mol·K (ideal gas constant)
T = 1200 K (given temperature)
So, to calculate the equilibrium pressure of CO2 in atmospheres (atm) at each temperature, you need to know the equilibrium constant for the reaction, represented by [CO2]. Once you have that value, you can substitute it into the equation P_CO2 = K * (RT) to find the equilibrium pressure.