ECAT Pre Engineering Chemistry Chapter 11 MCQ Test With Answer

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 :

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

which one of the following is a heteroheneous catalysis

• 
  A
• 
  B
• 
  C
• 
  D

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

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

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

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

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

The rate of reaction determined at a given time is called

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

Which of the following may affect the rate constant (k) fro a reaction :

• Change in concentration. A
• Change in pressure. B
• Change in pH. C
• Change in temperature. D

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

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

• 3 A
• 2 B
• 1 C
• 1 D

• 2 A
• 3 B
• 4 C
• 9 D

Half life period of a reaction is inversely proportion to the initial concentration of the reactant, then order of reaction is

• Third order A
• Second order B
• Fist order C
• Zero order D

In the hydrolysis of CH₃COOC₂H₅the acid produced is

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

The rate of reaction between two specific time intervals is called

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

The rate of reaction determined at a given time is called

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

Group l-A elements react with water fastly than the reaction of group ll-A elements because

• l_Aelements are more soft then ll_A A
• l_Aelements are non-metals B
• l_Aelements have 1 electron in their outermost s-orbital and are strongly electropositive C
• l_Aelements make ionic bond 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

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

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

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

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

The rate determining step is the :

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

The example of a photo chemical reaction is photosynthesis has order of reaction :

• 1 A
• 2 B
• 0 C
• 3 D