ECAT Chemistry Chapter 11 Reaction Kinetics

The change in concentration of reactant or product per unit time is called :

• Rate constant. A
• Rate of reaction. B
• Rate equation. C
• Rate law. 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

With increases in temperature of 10 K of the reacting gases the rate of reaction is doubled because

• Increase in number of collisions A
• Number of molecules having energy more than Ea is doubled B
• Increase in order of reaction C
• Increase in surface area D

• 2 A
• 3 B
• 4 C
• 9 D

All reactions occur in :

• A single step. A
• A series of steps B
• Two steps. C
• Both (a) and (b) D

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

• 
  A
• 
  B
• 
  C
• 
  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 statement is not correct

• Enzymes catalyst a specific reaction A
• Enzymes show catalytic activity at a specific temperature B
• The catalytic activity of enzymes is stopped if optimum pH is changed C
• The catalytic activity is poisoned by a co-enzymes 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

• 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

The rate of reaction between two specific time intervals is called

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

For effective collisions the molecules slow down before collision and their kinetic energy decreases which results in increase in their

• Activation energy A
• Average energy B
• Potential energy C
• Collisions frequency 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

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 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

The chemical method used for determination of rate of reaction is

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

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

• Order A
• Molecularity B
• Rate constant C
• Rate law 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

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 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

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

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 factor which effect the rate of reaction

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

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

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

• 3 A
• 2 B
• 1 C
• 1 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

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

The rate determining step is the :

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