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Calculate the equilibrium pressure of each reactant of given reaction with the help of following data.
A + B C + D
Initial pressure of A and B are 6 atm and 5 atm. The equilibrium pressure of C and D are 2 atm in each case.
Exercise 2 .
The equilibrium constant for the reaction
PCl5(g) PCl3(g) + Cl2(g) is 2.4 × 10–3. Determine the equilibrium constant for the reverse reaction at same temperature.
At 21.5°C and a total pressure of 0.0787 atm, N2O4 is 48.3% dissociated into NO2. Calculate Kp and Kc for the reaction.
Exercise 4 .
(i) Write the expression for Kp and Kc for the following reactions.
N2 + 3H2 2NH3
(ii) Find out the heterogeneous equilibrium from the following reaction
(A) CaCO3 (s) CaO(s) + CO2 (g)
(B) H2(g) + I2(g) 2HI (g)
What is the value of equilibrium constant for the following reaction
If A D
A B K1 = 2
B C K2 = 5
C D K3 = 3
In an equilibrium A + B —> C + D; A and B are mixed in a vessel at temperature T. The initial concentration of A was twice the initial concentration of B. After the equilibrium has established, concentration of C was thrice the equilibrium concentration of B. Calculate Kc.
Ammonium hydrogen sulphide dissociates as follows
NH4HS(s) NH3(g) + H2S(g)
If solid NH4HS is placed in an evacuated flask at certain temperature it will dissociate until the total pressure is 600 torr.
(a) Calculate the value of equilibrium constant for the dissociation reaction
(b) Additional NH3 is introduced into the equilibrium mixture without changing the temperature until partial pressure of NH3 is 750 torr, what is the partial pressure of H2S under these conditions? What is the total pressure in the flask?
At 700 K hydrogen and bromine react to form hydrogen bromide. The value of equilibrium constant for this reaction is 5 × 108. Calculate the amount of H2, Br2 and HBr at equilibrium if a mixture of 0.6 mole of H2 and 0.2 mole of Br2 is heated to 700 K.
The equilibrium constant is 0.403 at 1000K for the process
FeO(s) + CO(g) Fe(s)+ CO2)g)
A steam of pure CO is passed over powdered FeO at 1000K until equilibrium is reached. What is the mole fraction of CO in the gas stream leaving the reaction zone?
Exercise 10 .
N2 + 3H2 2NH3; Δ H = negative
What are the conditions of temperature and pressure favorable for this reaction?
Exercise 11: Equilibrium constant Kp for the reaction 3/2 H2(g) + 1/2 N2(g) NH3(g) are 0.0266 and 0.0129 at 310°C and 400°C respectively. Calculate the heat of formation of gaseous ammonia. Standard Free Energy Change of a Reaction and its Equilibrium Constant
What is the value of R if value of ΔGO is in?
(i) Joules (ii) Calories
N2O4 is 25% dissociated at 27°C and 1 atm pressure.
Calculate (i) Kp and (ii) the percentage dissociation at 0.1 atm and 27°C.
ANSWERS TO EXERCISES
A ——> 4 atm
B ——> 3 atm
4.16 × 102
Kp = 0.0956 atm
Kc = 3.96 × 10–3 mole/lit
Exercise 4: (i) Kc = [NH3]2 / [N2] [H2]3
(ii) (A) is a heterogeneous equilibrium.
K = 30
(a) 0.155 atm2
(b) 119.32 torr, 869.32 torr
0.4, 0, 0.4
Low temperature, high pressure and high concentration of N2 and H2.
(i) 8.314 J mole-1K-1
(ii) 2 cal mole-1K-1
(i) 0.266 atm