Q.1
The equilibrium constant at 323°C isWhat would be its value in the presence of catalyst of a catalyst in the forward reaction?A + B ⇔ C + D + 38 kcal
  • a) 1000 × conc. of catalyst
  • b) 1000
  • c)1000/ conc. of catalyst
  • d)can't be predicted
Q.2
Conjugate base for Bronsted acids H2O and HF are : [NEET 2019]
  • a) OH- and H2F+, respectively
  • b) H3O+ and F-, respectively
  • c) OH- and F-, respectively
  • d) H3O+ and H2F+, respectively
Q.3
Which will make basic buffer? [NEET 2019]
  • a) 50 mL of 0.1 M NaOH + 25 mL of 0.1 M CH3COOH
  • b) 100 mL of 0.1 M CH3COOH + 100 mL of 0.1 M NaOH
  • c) 100 mL of 0.1 M HCl + 200 mL of 0.1 M NH4OH
  • d) 100 mL of 0.1 M HCl + 100 mL of 0.1 M NaOH
Q.4
For a reaction A + B ↔ 2C2 moles of A and 3 moles of B are allowed to react. If equilibrium constant is 4 at 400°C, then the mole of C at equilibrium is [ AFMC 1997]
  • a) 1
  • b) 2.4
  • c)3.6
  • d)4
Q.5
Solubility product of a salt AB is 10-8M2 in a solution in which the concentration of A+ ions is 10-3M. The salt will precipitate when the concentration of B- ion is kept .. [ AFMC 2008]
  • a) between 10-8 to 10-7 M
  • b) between 10-7 to 10-8 M
  • c) > 10-5 M
  • d) < 10-8 M
Q.6
An amount of solid NH4HS is placed in a flask already containing ammonia gas at a certain temperature and 0.5 atm pressure. Ammonium hydrogen sulphide decomposes to yield NH3 and H2S gases in the flask. When the decomposition reaction reaches equilibrium, the total pressure in the flask rises to 0.84 atm. The equilibrium constant for NH4HS decomposition at this temperature is [ AIEEE 2005]
  • a)0.30
  • b) 0.18
  • c)0.17
  • d)0.11
Q.7
Phosphorus pentachloride dissociates as follows in closed reaction vessel PCl5 → PCl3 + Cl2 If total pressure at equilibrium of the reaction mixture is P and degree of dissociation of PCl5 is 'x', the particle pressure of PCL3 will be [ AIEEE 2006]
  • a)
    ch-8_qn-14choice_img_no1.png
  • b)
    ch-8_qn-14choice_img_no2.png
  • c)
    ch-8_qn-14choice_img_no3.png
  • d)
    ch-8_qn-14choice_img_no4.png
Q.8
For reaction, H2 + I2 ⇔ 2HI , the equilibrium constant Kp changes with ..[ IIT 1981]
  • a) Total pressure
  • b) Catalyst
  • c)The amount of H2 and I2 present
  • d)Temperature
Q.9
The equilibrium constant for the reaction PCl5 ⇔ PCl3 + Cl2 is 16 If the original volume of the container is reduced to half of its original volume, the value of Kp for the reaction at the same temperature will be
  • a) 32
  • b) 64
  • c) 16
  • d) 4
Q.10
In a reaction A2 + 4B2 ⇔ 2AB4 ;   ΔH
  • a)Low temperature and high pressure
  • b) High temperature and low pressure
  • c)Low temperature and low pressure
  • d)High temperature and high pressure
Q.11
the equilibrium constant, Kc for reaction N2 + O2 ⇔ 2NO at temperature T is 4 ×10-The value of KC for reaction NO ↔ ½ N2 + ½ O2 at the same temperature is [ AIEEE 2004]
  • a) 2.5 × 102
  • b) 0.02
  • d)50
  • c)4 × 10⁻⁴
Q.12
In the gas phase reaction C2 H4 + H2 ⇔ C2H6, the equilibrium constant can be expresseed in units
  • a) L-1 Mol-1
  • b) L Mol-1
  • c)L-2 Mol-2
  • d)Mol L-1
Q.13
In a reversible reaction, two substances are in equilibrium. If the concentration of each one is reduced to half, the equilibrium constant will be [ Pajab CET 1997]
  • a)Reduced to half of it original value
  • b) Doubled
  • c)Same
  • d)Reduced to one forth of its original value
Q.14
Sulphide ions in alkaline solution react with solid sulphur to form polyvalent sulphide ions. the equilibrium constant for the formation of S22- from S and S32- from S and S2- ions are 1.7 and 5.3 respectively. Equilibrium constant for the formation of S22- from S32- and S is
  • a) 1.33
  • b) 3.11
  • c)4.21
  • d)1.63
Q.15
in a system A(l) ⇔ B(l) + 2C(l) doubling the equilibrium concentration of B will cause the equilibrium concentration of C to change to
  • a) Two times its original
  • b) One half of its original value
  • c)(1/√2) times the original value
  • d)√2 times the original value
Q.16
For the reaction, N2 + 3H2 ⇔ 2NH3 at 500°C , the value of Kp is 1.44 × 10-What will be the value of Kp at low pressure where the gases are behaving almost ideally?
  • a) 1.44 × 10⁻⁵
  • b) (0.082 × 773)2 × 1.44 × 10⁻⁵
  • c)1.44 × 10⁻⁵ × (0.082 × 500)2
  • d)1.44 × 10⁻⁵ × (0.082 × 773)3
Q.17
The oxidation of SO2 by O2 to SO3 is an exothermic reaction. The yield of SO3 will be maximum if [ IIT 1981]
  • a) Temperature is increased and pressure is kept constant
  • b)Temperature is reduced and pressure is increased
  • c)Both temperature and pressure are increased
  • d)Both temperature and pressure are decreased
Q.18
If equilibrium constant for a reaction is K, then standard free energy change is
  • a) ΔGo=-RTlogK
  • b) ΔGo=RTlnK
  • c) ΔGo=RTlogK
  • d) ΔGo=-2.303RTlogK
Q.19
When two reactants A and B are mixed to give products C and D the reaction quotient, Q at the initial stage of reaction ..[ IIT 2000]
  • a)Decreases with time
  • b) Is independent of time
  • c)Is zero
  • d)Increases with time
Q.20
The equilibrium constant for reversible reaction N2 + 3H2 ⇔ 2NH3 is K and for the reaction ½ N2 + (3/2)H2 ⇔ NH3 The equilibrium constant is K'. K and K' will be related as [ MP CET 1998]
  • a) K=K'
  • b) K'=√(K)
  • c)K=√(K')
  • d)K × K'=1
Q.21
Which oxide of nitrogen is most stable at 273 K ?
  • a)
    ch-8_qn-31choice_img_no1.png
  • b)
    ch-8_qn-31choice_img_no2.png
  • c)
    ch-8_qn-31choice_img_no3.png
  • d)
    ch-8_qn-31choice_img_no4.png
Q.22
The equilibrium constant for reaction SO3 → SO2 + ½O2 is Kc=4.9 × 10-the value of Kc for the reaction 2SO2 + O2 → 2SO3 will be [ AIEEE 2006]
  • a) 416
  • b) 2.4 × 10⁻³
  • c) 9.8 × 10⁻²
  • d) 4.9× 10⁻²
Q.23
the equilibrium constant Kp for the reaction PCl5 ↔ PCl3 + Cl2 is 16 If the volume of the container is reduced to half of its original volume, the value of Kp for the reaction at the same temperature will be
  • a)32
  • b) 64
  • c)16
  • d)4
Q.24
For a reaction N2 + 3 H2 → 2NH3; °H=-22 kcal. If energy of activation for this reaction is 70 kcal, the energy of activation for backward reaction is
  • a) 70 kcal
  • b) 92 kcal
  • c)48 kcal
  • d)None of these
Q.25
the value of reaction quotient before any reaction occurs is
  • a) ∞
  • b) -1
  • c)0
  • d)1
Q.26
Consider the following equilibrium in closed container N2O4 ⇔ 2NO2 . At a fixed temperature, the volume of the reaction container is halved. For this change, which of the following statement holds true regarding the equilibrium constant (Kp) and degree of dissociation ( α) [ IIT 2002]
  • a) Neither Kp nor α changes
  • b) Both Kp nor α changes
  • c) Kp changes but α does not change
  • d) Kp does not change but α changes
Q.27
For reaction Co + K2O ⇔ Co2 + H2 at given temperature, the equilibrium amount of CO2 can be increased by [ IIT 1998]
  • a)Adding a suitable catalyst
  • b) Adding an inert gas
  • c)Decreasing the volume of the container
  • d)Increasing the amount of CO
Q.28
The yields of NH3 in the reaction N2 + 3H2 ↔ 2NH3 ; ΔH=-22.08 kcal is affected by [ Pb CET 1997]
  • a) Change in pressure and temperature
  • b) Change in temperature and concentration of H2
  • c)Change in pressure and concentration of N2
  • d)Change in pressure, temperature and concentration of N2
Q.29
If 1.0 mole of I2 is introduced into 1.0 litre flask at 1000K which leads to dissociation, at equilibrium, ( Kc=10-6), which one is correct?
  • a) [ I2(g)] > I-]
  • b) [ I2(g)] < I-]
  • c) [ I2(g)]=I-]
  • d) [ I2(g)]=½ I-]
Q.30
At constant temperature, the equilibrium constant ( Kp) for the decomposition reaction N2O4 ⇔ is expressed by Kp=4x2P/(1-x2) where P is pressure, x is extent of decomposition. Which of the following statement is true [ IIT 2001]
  • a) Kp increases with increase with increase of P
  • b) Kp increases with increase with increase of x
  • c) Kp increases with decrease with increase of P
  • d) Kp remains constant with change in P or x
0 h : 0 m : 1 s