Question

#1 A sample of ammonium carbamate placed in an evacuated glass vessel at 25C undergoes the reaction: NH4OCONH2(s) <==> 2NH3(g) + CO2(g)

The equilibrium constant for this reaction at 25C is 2.25x10^-4 calculate the partial pressures of NH3 and CO2.

#2 Steam and CO2 in equilibirum with solid sodium hydrogen carbonate at 110C corresponds to the reaction: 2NaHCO3(s)<==> Na2CO3(s) + H2O(g)+ CO2(g)

(NaHCO3 is used in dry chemical fire extinguishers because the products of this decomposition reaction smother the fire.) The equilibrium for this reaction at 110C is 0.679 a) determine the partial pressures for each gas at equilibrium.

b) what is the partial pressure of the water vapor in equilibirum with NaHCO3(s) at 110C if the partial pressure of CO2(g) is 0.800 atm?

Model 1: Le Chatelier's Principle

#3 The endothermic (deltaH > 0) reaction below is at equilibrium

SO3(g) <==> SO2(g) + 1/2 O2(g)

a) in what direction does the equilibrium shift when O2(g) is removed from the system at constant volume and temperature? Explain your answer.

b) in what direction does the equilibrium shift when the volume is increased at constant temperature? Explain your answer

c) in what direction does the equilibirum shift when the temperature is increased? Explain your answer.