ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

In an experiment the concentration of a reactant 'A' is doubled the rate increases four times. If concentration in tripled, then rate increases nint times. Thus the rate is proportional to ______ of concentration of 'A'

• Square root A
• Square B
• Twice C
• Cube D

Half life period of N₂O₅is 24 minutes and it remains same where we increase or decrease its initial concentration, then reactions

• Zero order A
• First order B
• Second order C
• Third order D

Homogenous catalysis is that in which catalyst and reactants are in same phase. Which one of the following reaction is a homogenous catalysis

• 
  A
• 
  B
• 
  C
• 
  D

The chemical method used for determination of rate of reaction is

• Spectroscopic A
• Conductiometric B
• Refractometric C
• Titration D

• Three times A
• Six times B
• Nine times C
• Two times D

A pseudo uni-molecular reaction has order of reaction :

• 3 A
• 2 B
• 1 C
• 0 D

The rate of reaction :

• Increase as the reaction proceeds. A
• Decreases as the reaction proceeds. B
• Remains the same as the reaction proceed. C
• May decrease or increase as the reaction proceeds. D

A zero order reaction is one in which :

• Rate is not affected by changing concentration of reactants. A
• concentration of reactants do not change with the passage of time. B
• Reactants do not react. C
• One reactants in large excess. D

Activation energy is the difference of energy between the energy of the reactant and

• The product A
• The activated complex B
• Both a and b C
• None of these D

The rate equation for a reaction is Rate =k[A]. what are unit of K ?

• Mole-1 dm³ S^-1

  A

• Mole dm³ S^-1

  B

• Mole dm³

  C

• S^-1

  D

• 2 A
• 3 B
• 4 C
• 9 D

The rate constant k of a reaction activation energy Ea and temperature are related by Arrhenius in the form of an equation which is

• 
  A
• 
  B
• 
  C
• 
  D

The unit of rate constant k is the same as that of the rate of reaction in

• First order reaction A
• Second order reaction B
• Third order reaction C
• Zero order reaction D

Dilatometer method is useful for the reaction that involve :

• Small volume changes in solutions A
• Change in infractive indices B
• Where reactants absorb U.V, visible or infrared radiation C

If a reactant or product of a reaction absorbs radiation, then physical method for determining the rate of reaction is

• Spectrometry A
• Refractometry B
• Conductivity measurement C
• Optical method D

Which of the following will affect the rate :

• First step of reaction. A
• Last step of reaction. B
• Rate determining step. C
• Fastest step. D

If the rate equation of a reaction 2A+B-------->Products is , Rate = K[A] [B], and A is present in large excess, then order of reaction is :

• 1 A
• 2 B
• 3 C
• Above D

In the reaction of oxalic acid with KMnO₄and H₂SO₄is slow at the beginning but after sometimes the reaction becomes faster due to

• Formation of MnSO₄which acts as 'Auto catalyst A
• Formation of CO₂which acts as 'Auto catalyst B
• Formation of K₂SO₄which acts as 'Auto catalyst C
• Evolution of O₂gas which acts as 'Auto catalyst D

• 
  A
• 
  B
• 
  C
• 
  D

If the rate of reaction is independent of the concentration of the reactant, the reaction is of

• Zero order A
• First order B
• Second order C
• Third order D

The unit of rate constant is the same as that of the rate of reaction in :

• First order reaction. A
• Second order reaction. B
• Zero order reaction. C
• Third order reaction. D

The experimental relationship between a reaction rate and the concentration of reactants is called

• Order or reaction A
• Rate law B
• Activated complex C
• Molecularity D

The rate of reaction determined at a given time is called

• Average rate A
• Instantaneous rate B
• Specific rate C
• Overall rate D

It rate law of an equation is written asdx/dt=K[A][B] ?

• Reaction is independent of the concentration of A and B. A
• Product is decreasing with passage of time. B
• Reactant in increasing with passage of time. C
• Reactant is increasing with passage of time. D

Which of the following reactions occur at moderate rate :

• Rusting of iron A
• Chemical weathering of stone work of buildings by acidic gases in atmosphere. B
• Hydrolysis of an ester C
• Fermentation of sugars D

______ are called biocatalysts

• Organic acids A
• Organic bases B
• Enzymes C
• All D

Hydrolysis of ethyl-acetate (ester) has order of reaction :

• 3 A
• 2 B
• 1 C
• 1 D

The actual number of atoms or molecules taking part in rate determining step is

• Rate of reaction A
• Velocity of reaction B
• Order of reaction C
• Molecularly D

For a chemical reaction to take place the particles must have sufficient energy for the effective collisions, the energy is called

• Average energy A
• Activation energy B
• Potential energy C
• Collision energy D

Which of the following factors does not influenced the rate of reaction

• Concentration of the reaction A
• Nature of the reactants B
• Molecularity of the reaction C
• Temperature D