ECAT Pre Engineering Chemistry Chapter 8 MCQ Test With Answer

The solubility of PbF₂is 2.6 x 10^-3mole dm^-3 then its solubility product is

• 2.6 x 10^-3 A
• 6.76 x 10^-6 B
• 5.2 x 10^-6 C
• 7.0 x 10^-8 D

• Low pressure A
• High pressure B
• High temperature C
• High concentration of SO₂ 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

• 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

Which one of the following has no units of its K_cvalue

• 
  A
• 
  B
• 
  C
• 
  D

K_bfor NH₄OH is 1.81 x 10^-5, then K_avalue of its conjugate base is

• 1.81 x 10⁺⁵ A
• 1.81 x 10^-9 B
• 5.5 x 10^-9 C
• 5.5 x 10^-10 D

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

pH of water is 7, if 0.01 M NaOH is added, than its pH is

• 12 A
• 14 B
• zero C
• 10 D

• 0.02 A
• 0.2 B
• 50 C
• 25 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

N₂ +3H₂⇌ 2NH_{3 + Heat for above equation, themaximum product will be obtained at :}

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

The avtive mass of 64 g of HI in a two litre flask would be

• 2 A
• 1 B
• 5 C
• 0.25 D

Whenever a week base is dissolved in water, it give its conjugate acid. similarly a weak acid in water produces its conjugate base. This conjugate acid-base pair concept is stated by

• Law of mass action A
• Le-charlier's principle B
• Common ion effect C
• Lowery Bronsted concept D

• Reaction occurs at STP A
• Reaction is exothermic B
• Reaction is endothermic C
• Number of moles of production and reactant are same D

The ionization constant of an acid is expressed in term of the following constant

• Kw A
• Kn B
• Ka C
• Kb D

The rate of forward reaction is two times that of the reverse reaction at a given temperature and identical concentration, K equilibrium is

• 0.5 A
• 1.5 B
• 2.5 C
• 2.0 D

• 
  A
• 
  B
• 
  C
• 
  D

An aqueous solution is neutral when its

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

• Forward reaction is favoured A
• Backward reaction is favoured B
• No effect C
• None of the above D

pH of 0.1 molar HCl solution is

• 1 A
• zero B
• 13 C
• 14 D

• Complete conversion of A to B has taken place A
• Conversion of A to B is only 50% complete B
• Only 10% conversion of A to B has taken place C
• The rate of transformation of A to B is just equal to rate of transformation of B to A in the system D

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

For the above reaction the relationship b/w k_c and k_p will be :

• K_p = K_cRT

  A

• Kp = K_c(RT)_-1

  B

• K_p = K_c(RT)_-2

  C

• K_c = K_p

  D

Which statement about the following equilibrium in correct?

2SO_{2 (g)}+ O_2(g)---------------2sO_3(g)H= - 188.3 KJ mol-1

• T value of K_{p falls witha rise in temperate.} A
• The value of K_{p falls withincreasing pressure}
  B
• Adding V_2O5catalyst increase the equilibrium yield of sulfur trioxide
  C
• The value of K_{p is equal to}K_p D
• 
  
  E

Which one of the following is not a buffer

• H₂CO₃+ NaHCO₃solution A
• H₃PO₄+ NaH₂PO₄solution B
• Hl + Nal solution C
• NH₄OH + NH₄CI solution D

N₂3H₂⇌ 2NH₃

_{Which of the following change will favorthe formation of more}NH₃at equilibrium in above reaction :

• By adding NH_3. A
• By removingH_2. B
• By decreasing pressure. C
• By increasing pressure. D

• KC = KP A
• Kp = KcRT B
• Kp = kc(RT)^-2 C
• Kp = Kc(RT)^-1 D

Which of the following favours the reverse reaction in chemical equilibrium?

• Increasing the concentration of the reactant A
• Removal of the least one of the products at regular intervals B
• Increasing the concentration of one or more of the products C
• None of these D

Which of the following in an example of reversible reaction

• 
  A
• 
  B
• 
  C
• 
  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