ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

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

The catalytic activity of Pt is much higher when

• It is mixed with asbestos A
• It is mixed with Pd B
• It is mixed with arsenic C
• In is made colloidal platinum D

Which statement about Arrhenius equation is incorrect

• Factor 'A' called Arrhenius constant depends upon collision frequency of reactants A
• Rate of reaction increase by increasing temperature B
• Rate constant k is increased C
• Activation energy Ea is decreased by rise in temperature D

Which of the following is not affected by light

• 
  A
• 
  B
• 
  C
• 
  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

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

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

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

The rate determining step is the :

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

______ are called biocatalysts

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

When initial concentration of reactants an order of reaction is given, then its half life period can be calculated by the equation

• 
  A
• 
  B
• 
  C
• 
  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

• Diastase A
• Lipase B
• Inverters C
• Zymase 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

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 of reaction determined at a given time is called

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

To determine the rate of reaction chemically a graphical method is applied. A graph is plotted between the amount or reactant decomposed or product formed against the time. The rate d_x/d_tat any time is equal to

• k A
• Tangentθ B
• 1/a, a is initial conc. C
• 1/a² D

If half life period of a reaction is independent of the concentration of the reactants, then the reaction is

• Zero order A
• First order B
• Second order C
• Order is in fraction D

• Initial concentration of reaction A
• Initial concentration of products B
• Final concentration of products C
• Order of the reaction D

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

Value of rate constant k is specific for a reaction, and varies from reaction to reaction. The value of k of a reaction changes with

• Time A
• Temperature B
• Concentration of reactants C
• Order of reaction 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

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

If initial concentration of the reactants and half life period of the reaction is known, then we can determine

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

When we perform the same reaction by taking two different initial concentrations of a reactant for a second order reaction then

• Reaction becomes exothermic A
• Energy of activation is different B
• Mechanism of reaction is changed C
• Half life period is changed 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

A white precipitate ofsilver chlorideimmediately formed on additionof :

• Silver nitrate solution to sodium chloride solution. A
• Silver chloride solution to sodium nitrate solution. B
• Silver nitrate solution to potassium chloride solution C
• Silver nitrate solution to hydrogen chloride solution. D

Dilatometric method is used for rate determination when

• Reactions involving change of optical A
• Reactions involving change of optical activity B
• Reactions involving small volume change C
• None of above D