In a reversible reaction at equilibrium, the rate of the forward reaction is:
- AGreater than the reverse reaction
- BEqual to the reverse reaction
- CLess than the reverse reaction
- DZero
The equilibrium constant (Kc) for the reaction N2 + 3H2 ⇌ 2NH3 is:
- A[NH3][N2][H2]
- B[NH3]2[N2][H2]3
- C[N2][H2]3[NH3]2
- D[N2][H2][NH3]
If the value of Kc is very large, the equilibrium mixture contains:
- AMostly reactants
- BMostly products
- CEqual amounts of reactants and products
- DOnly reactants
The equilibrium constant for a reaction is 1.0 × 10-3. This indicates that the reaction:
- AGoes almost to completion
- BProceeds very little in the forward direction
- CIs very fast
- DIs at equilibrium
In a system at equilibrium, adding a catalyst:
- AShifts the equilibrium to the right
- BShifts the equilibrium to the left
- CDoes not change the equilibrium position
- DChanges the value of Kc
According to Le Chatelier's principle, increasing the pressure on the equilibrium 2SO2(g) + O2(g) ⇌ 2SO3(g) will shift the equilibrium:
- ATo the left
- BTo the right
- CNo shift
- DTo the left then right
The equilibrium constant expression for the reaction CaCO3(s) ⇌ CaO(s) + CO2(g) is:
- AKc = [CaO][CO2][CaCO3]
- BKc = [CO2]
- CKc = [CaCO3][CaO][CO2]
- DKc = 1[CO2]
For the reaction A2 + B2 ⇌ 2AB, the equilibrium concentrations are [A2] = 0.399M, [B2] = 1.197M, [AB] = 0.203M. The value of Kc is approximately:
The relationship between Kp and Kc is given by:
- AKp = Kc (RT)Δ n
- BKp = KfraccRTΔ n
- CKp = Kc + RT
- DKp = Kc - RT
For an exothermic reaction at equilibrium, increasing the temperature will:
- AShift the equilibrium to the right
- BShift the equilibrium to the left
- CIncrease Kc
- DNot affect the equilibrium
