ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

The unit rate of constan K ismole^-1 dm³S^-1for a chemical reaction, the order of reaction is :

• 3 A
• 2 B
• 1 C
• 0 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

The rate of reaction b/w two specific time intervals is called :

• Instantaneous rate of reaction. A
• Average rate of reaction. B
• Rate of a reaction. C
• Minimum rate of a reaction. 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

When copper is allowed to react with HNO₃, the reaction is slow in the beginning, finally becomes very fast. It is due to the formation of an auto catalyst which is

• Cu(NO₃)₂ A
• CuO B
• O₂ C
• HNO₂ D

With increases of 10°C temperature the rate of reactiondoubles. This increase in rate of reactionis due to :

• Decrease in activation energy or reaction. A
• Decrease in number of collisions between reactant molecules. B
• Increase in activation energy of reactants. C
• Increase in number of effective collisions D

Optical rotation method is sued when

• Reaction involve ions A
• Change of refractive indices B
• Reactions involving change of optical activity C
• None of the above 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

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

Half life period of a first order reaction is independent of:

• Presence of catalyst. A
• Conditions of temperature B
• Initial concentration of the compound C
• All of above 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

Which technique is used to determine the absorption of radiations?

• Dilatometer method

  A

• Optical rotation method

  B

• Spectrometry

  C

• Refractometric method

  D

It is common observation that rates of chemical reactions differ :

• Greatly. A
• A little bit. B
• Moderately. C

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

• 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

In the hydrolysis of CH₃COOC₂H₅the acid produced is

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

• Small change in concentration of product A
• Small time internal B
• Co-efficient of the reactant C
• Co-efficient of the product D

The rate of reaction is denoted by

• dc/dp A
• dc/ac B
• dc/dT C
• dc/dt 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

which one of the following is a heteroheneous catalysis

• 
  A
• 
  B
• 
  C
• 
  D

Which of the following is not affected by light

• 
  A
• 
  B
• 
  C
• 
  D

• First order A
• Pseudo first order B
• Second order C
• Zero order D

Factor which slows down the rate of reaction is

• Small size of the particles of the reactant A
• High temperature of reaction B
• More concentration of reactant C
• Lowering the temperature 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 rate determining step is the :

• Slowest step. A
• Fastest step. B
• Moderate step. C
• Both (a) and (b). D

In the expression rate = K [A]^a[B]^bK is

• The order of reaction A
• The speed of reaction B
• The specific rate constant C
• The overall order of 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

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

Complex protein molecules which catalyses the organic reactions in the living cells are called

• Living organisms A
• Enzymes B
• Viruses C
• Bacteria 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