Chemistry Question Bank

The free energy of formation of NO is 78 kJ mol–1 at the temperature of an automobile engine (1000 K). What is the equilibrium constant for this reaction at 1000 K ? N (g) O (g) NO(g)

A vessel at 1000 K contains CO2 with a pressure of 0.5 atm. Some of the CO2 is converted to CO on addition of graphite. If the total pressure at equilibrium is 0.8 atm, the value of K is :

For a reversible reaction : A + B C dx dt = 2.0 × 103 L mol–1 s–1 [A] [B] – 1.0 × 102 s–1 [C] where x is the amount of ‘A’ dissociated. The value of equilibrium constant (Keq) is :

The standard state Gibb’s free energy change for the isomerization reaction cis-2-pentene trans-2-pentene is –3.67 kJ mol–1 at 400 K. If more trans-2-pentene is added to the reaction vessel

Consider the reaction PCl5 (g) PCl3 (g) + Cl2 (g) in a closed container at equilibrium. At a fixed temperature what will be the effect of adding more PCl5 on the equilibrium concentration of Cl2 (g) ?

In which of the following system, doubling the volume of the container cause a shift to the right

The exothermic formation of ClF3 is represented by the equation Cl2(g) + 3F2(g) 2ClF3(g); H = – 329 kJ Which of the following will increase the quantity of ClF3 in an equilibrium mixture of Cl2, F2 and ClF3

The effect of increasing the pressure on the equilibrium 2A(g) + 3B(g) 3A(g) + 2B(g) is

Following gaseous reaction is undergoing in a vessel C2H4 + H2 C2H6; H = – 32.7 Kcal Which will increase the equilibrium concentration of C2H6

In the reaction A(g) + 2B(g) C(g) + Q kJ, greater product will be obtained or the forward reaction is favoured by

Which of the following statements regarding a chemical equilibrium is wrong

In equilibrium CH3COOH + H2O CH3COO– + H The equilibrium constant may change when

What is the effect of halving the pressure by doubling the volume on the following system at 500°C H2(g) + I2(g) 2HI(g)

In which of the following reaction Kp > Kc

The reaction between N2 and H2 to form ammonia has Kc = 6 × 10–2 at the temperature 500°C. The numerical value of Kp for this reaction is

For the reaction H2(g) + I2(g) 2HI(g) at 721K the value of equilibrium constant (Kc) is 50. When the equilibrium concentration of both is 0.5M, the value of Kp under the same conditions will be

In which of the following equilibria, the value of Kp is less than Kc

For N2(g) + 3H2(g) 2NH3(g) + heat

In which of the following gaseous reaction, the value of Kp will be equal to Kc

4 moles of A are mixed with 4 moles of B when 2 moles of C are formed at equilibrium according to the reaction A + B C + D The value of the equilibrium constant is

One mole of SO3 was placed in a vessel of 1 litre capacity at a certain temperature when the following equilibrium was established 2 SO3 2 SO2 + O2 At equilibrium, 0.6 moles of SO2 were formed. The equilibrium consta…

56 g of N2 and 6g H2 were kept at 400ºC in l litre vessel. The equilibrium mixture contained 27.54g of NH3. The approximate value of Kc for the above reaction in mol-2 lit2 is

Two moles of HI were heated in a sealed tube at 440ºC till the equilibrium was reached. HI was found to be 22% decomposed. The equilibrium constant for dissociation is

The decomposition of N2O4 to NO2 is carried out at 280º C in chloroform. When equilibrium is reached 0.2 mol of N2O4 and 2 × 10–3mol of NO2 are present in 2 litre solution. The equilibrium constant for the reaction N2…

For the system A (g) + 2 B (g) C (g) the equilibrium concentrations are A = 0.06 mol L–1 B = 0.12 mol L–1 C = 0.216 mol L–1. The Keq for the reaction is