ECAT Pre Engineering Chemistry Chapter 8 MCQ Test With Answer

• Forward A
• Backward B
• Already in equilibrium C
• K_cis never less D

The pH of 10^-3mole dm^-3of an aqueous solution of H₂SO₄is

• 3.0 A
• 2.7 B
• 2.0 C
• 1.5 D

Which of the following solution have zero pH

• 1 M HCI A
• MH₂SO₄ B
• 0.1 M HNO₃ C
• 1 M CH₃COOH D

• Introduction of an inert gas at constant volume A
• Introduction of PCl₃(g) at constant B
• Introduction of PCl₅(g) at constant volume C
• Introduction of Cl₂at constant volume D

• 0.073 A
• 0.147 B
• 0.05 C
• 0.026 D

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

• 0.282 A
• 0.0796 B
• 0.0199 C
• 1.99 D

For what value ofK_{c almost forward reaction is complete :}

• K_{c =} 10³⁰

  A

• K_{c =} 10^-30

  B

• K_{c =} 0

  C

• K_{c =} 1

  D

H₂ + L₂ ----2Hl

In the above equilibrium system, if the concentration of reactants at 25°C is increased, the value K_C will :

• Remains Constant A
• Increases B
• Cecreases C
• Depends upon nature of reactans D

Under what condition of temperature and pressure the formation of atomic hydrogen from molecular hydrogen will be favourd

• High temperature and high pressure A
• Low temperature and low pressure B
• High temperature and low pressure C
• :Low temperature and high pressure D

• 450°C A
• 250°C B
• 850°C C
• 1000°C D

A large value of K_cmeans that at equilibrium :

• Less reactant and more products. A
• Reactants and product in same amounts. B
• More reactants and less products. C
• None of above. D

• Increase in concentration of 1 A
• Decrease in concentration of I₂ B
• Increase in temperature C
• Increase in total pressure D

ph of the buffer CH₃COOh + CH₃COONa is 3.76. If the mixture contains 1 molar acetic acid and 0.1 molar sodium acetate, then pKa of this buffer is

• 3.76 A
• 4.76 B
• 5.76 C
• 6.76 D

A gas bulb is filled with NO₂gas and immersed in an ice bath at 0°C which becomes colourless after sometimes. This colourless gas will be

• NO₂ A
• N₂O B
• N₂O₄ C
• N₂O₅ D

The solubility product of AgCl is 2.0 x 10^-3 mol² dm^-6 , The maximum concentration of Ag ion in the solution is :

• 2.0 x 10^-10 mol dm^-3

  A

• 1.41 x 10^-10 mol dm^-3

  B

• 1.0 x 10^-10 mol dm^-3

  C

• 4.0 x 10^-10 mol dm^-3

  D

pH of the human blood which is essentially maintained constant due to carbonates, biocarbonates, phosphates etc., is

• 7.00 A
• 7.25 B
• 7.35 C
• 7.47 D

• 0.60 A
• 1.67 B
• 0.66 C
• 2.6 D

K_bvalue of NH₄OH is 1.81 x 10^-5and its conjugate acid has K_a= 5.7 x 10^-10pKb of the base is 4.74, pKa of its conjugate acid is

• -4.74 A
• 4.74 B
• 10 C
• 9.26 D

An aqueous solution is neutral when its

• pH = 14 A
• pH = zero B
• pH = 7 C
• Kw = 10^-7 D

A buffer of a 0.09 molar acetic acid and 0.11 molar sodium acetate has pH = 4.83. If 0.01 mole NaOH in 1 dm³of the buffer solution is added, then pH of the buffer becomes

• 4.74 A
• 4.92 B
• 5.0 C
• 4.0 D

• 
  A
• 
  B
• 
  C
• 
  D

• High temperature and low pressure A
• Low temperature and low pressure B
• Low temperature and high pressure C
• High temperature and high pressure D

K_spvalue for PbSO₄= 1.8 x 10^-8mole²dm^-6. The maximum concentration of Pb⁺⁺ions is

• 1.34 x 10^-4mole dm^-3 A
• 1.8 x 10^-4 B
• 3.6 x 10^-16mole dm^-3 C
• 1.0 x 10^-8mole dm^-3 D

0.1 MHCI has pH = 1.0, it is about 100 times stronger than acetic acid. Then pH of acetic acid will be

• 0.1 A
• 2.0 B
• 1.3 C
• 3.0 D

• The value of K_pfalls with rise in temperature A
• The value of K_pfalls with increasing pressure B
• Addition of V₂O₅catalyst increase the concentration of SO₃ C
• The value of K_pis equal to K_c D

Extent to H₂ + L₂ à2Hl can be increased by :

• Increasing temperature.

  A

• Increasing product.

  B

• Increasing pressure.

  C

• Adding a catalyst.

  D

• The value of K_pfalls with a rise in temperature A
• The value of K_pfalls with increasing pressure B
• Adding V₂O₅catalyst increase the equilibrium yield of sulphur trioxide equilibrium yield of sulphur trioxide C
• The value of K_pis equal to K_c D

For which system does the equilibrium constant. K_c has units of

• 
  A
• 
  B
• 
  C
• 
  D

• Reversible reaction A
• Irreversible reaction B
• Spontaneous reaction C
• None of these D

I a chemical reaction equilibrium is said to have been established when :

• Rate of opposing reactions are equal. A
• Rate constants of opposing reactions are equal. B
• Opposing reactions stop. C
• Concentration of reactants and products are equal D