ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

The unit of rate constant K ismole^-1 dm³for a chemical reaction, the order of reaction is :

• Order of reaction can determined by an experiment A
• Order of reaction can determined from a balance equation only. B
• Order of reaction can determined increases by increasing temperate. C
• Order of reaction must be in whole number and not in fraction. D

The reaction rate is expressed in the units of

• Mol dm^-3S^- A
• Mol dm^-3 B
• Mol dm^-3N^- C
• dm^-3S^- 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

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

With the progressive of the reaction the slope of the curve between concentration of product and time

• Gradually becomes more steep A
• Gradually becomes less steep B
• No change occurs in slope C
• None of these occurs D

Which one of the following reaction rate is effected by the light

• 
  A
• 
  B
• 
  C
• 
  D

The number of atoms or molecules whose concentrations determine the rate of the reaction is called

• Molecularity A
• Order B
• Rate of reaction C
• Rate constant 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

When the rate of reaction is entirely independent of the conc. of reaction molecules then order of reaction is

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

A catalyst is a substance which increase the rate of a chemical reaction, but remains unchanged at the end of reaction, nut remains unchanged at the end of reaction, because

• It increases the temperature A
• It increase the surface area B
• It increases the rate constant C
• It decrease the energy energy of activation D

By the use of catalysis the energy of activation is

• Decreased A
• Increased B
• Not affected C
• None D

• Zero A
• 253 sec B
• 150 sec C
• 500 sec 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

______ are called biocatalysts

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

Which of the following is not affected by light

• 
  A
• 
  B
• 
  C
• 
  D

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

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

The rate of reaction between two specific time intervals is called

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

• 1st order A
• 2nd order B
• Zero order C
• 3rd order D

In the hydrolysis of CH₃COOC₂H₅the acid produced is

• Inhibitor A
• Catalyst B
• Auto catalyst C
• None of above 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

In the rate equation when the concentration of reactants are unity, then rate is equal to

• Instantaneous rate A
• Average rate B
• Active mass of products C
• Specific rate constant D

The effective activity of a metal catalyst is increased if it is in

• Solid form A
• Liquid state B
• Gaseous state C
• Finely divided form 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

In exothermic reaction decrease in potential energy of the products will result in

• Decreases in kinetic energy of the particles A
• Increases in kinetic energy of the particles B
• No change in kinetic energy C
• Decreases in activation energy D

• Rate = k[FeCl₃] [Kl]² A
• Rate = k[Fe⁺³][Cl^-1] [Kl] B
• Rate = k[Fe⁺³] [Cl^-1][K;] C
• Rate = k[Kl]³[FeCl₃]° D

Rate of chemical reaction depends upon :

• The number of total collisions per second. A
• Number of molecules taking part in a chemical reaction. B
• Number of fruitful collisions per second C
• Number of fruitless collisions per second. D

The rate of reaction :

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

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 technique is used to determine the absorption of radiations?

• Dilatometer method

  A

• Optical rotation method

  B

• Spectrometry

  C

• Refractometric method

  D