ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

Refrectrometric method is used when

• Reactions involving absorption of I.R. or U. V A
• Reactions involving change of refractive index B
• Reactions involving ions C
• Change of optical activity D

In the manufacture of NH₃by Haber's process catalyst used is iron its catalytic efficiency is poisoned by

• Presence of Al₂O₃ A
• Presence of Cr₂O₃ B
• MnO₂ C
• CO present with H₂gas D

The sum of the exponents of the conc. terms in the rate equation is called

• Rate of reaction A
• Order of reaction B
• Specific rate constant C
• Average rate D

The rate determining step is the :

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

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

• 
  A
• 
  B
• 
  C
• 
  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

Hydrogenation of vegetable oils is accelerated by Ni catalyst. The catalytic activity of Bi is increased by a promoter of activator which is

• Na and K A
• Na and Hg B
• Hg and Zn C
• Cu and Te D

The value of activation energy Ea of a reaction can be determined from the value of slope of the straight line obtained by plotting a graph between 1/T and log k. the value of Ea is equal to

• Slope A
• 1/Slope B
• Slope x R C
• Slope x 2.303 R D

• Rate is independent of concentration of water since it is in excess A
• Rate is independent of concentration of ester since it is in exces B
• Rate depends upon the concentration of acid catalyst added C
• Rate = k[CH₃COOC₂H₅]^1/2[H₂O]^1/2 D

If the rate of decay of radioactive isotope decreases from 200 cpm to 25 cpm after 24 hours, what is its half life :

• 8 hours A
• 6 hours B
• 4 hours C
• 3 hours 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 zero order reaction, the rate is independent of :

• Temperature of reaction A
• Concentration ofreactants B
• Concentration of products C
• None of these. D

The factor which effect the rate of reaction

• Nature of reactants A
• Surface area B
• Light C
• All of the above 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

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

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

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

• 
  A
• 
  B
• 
  C
• 
  D

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

Rate law of an equation is obtained :

• From a balance equation. A
• Can be calculated theoretically as well as determined experimentally. B
• It is only calculated theoretically. C
• Experimentally. 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

It is common observation that rates of chemical reactions differ :

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

• 2 A
• 3 B
• 4 C
• 9 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

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

which one of the following is a heteroheneous catalysis

• 
  A
• 
  B
• 
  C
• 
  D

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

• Homogeneous A
• Heterogeneous B
• Isogeneous C
• None D