Chemistry

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The minimum amount of energy in addition to the average energy, which is just sufficient to convert reactants to products, is called

The minimum amount of energy in addition to the average energy, which is just sufficient to convert reactants to products, is called
  • A. internal energy
  • B. dissipation energy
  • C. enthalpy
  • D. activation energy
  • Correct Answer: Option D

generally rise of 10°C of the temperature of a reaction system, the reaction rate

generally rise of 10°C of the temperature of a reaction system, the reaction rate
  • A. increases
  • B. doubles
  • C. subsides
  • D. drops
  • Correct Answer: Option B

greater the number of molecules of the reacting substances per unit volume greater will be the

greater the number of molecules of the reacting substances per unit volume greater will be the
  • A. collisions
  • B. reaction rate
  • C. energy losses
  • D. product formed
  • Correct Answer: Option B

Ir respect of the fact that a chemical reaction is exo- or endo-thermic, the increase in temperature, increases the

Ir respect of the fact that a chemical reaction is exo- or endo-thermic, the increase in temperature, increases the
  • A. potential energy
  • B. collisions
  • C. reaction rate
  • D. kinetic energy
  • Correct Answer: Option C

Similar substance can have different reaction rates under

Similar substance can have different reaction rates under
  • A. same conditions
  • B. different conditions
  • C. various conditions
  • D. ideal conditions
  • Correct Answer: Option A

The rate of a chemical reaction is proportional a to the product of molar concentrations of the

The rate of a chemical reaction is proportional a to the product of molar concentrations of the
  • A. products
  • B. reacting species
  • C. intermediates
  • D. all species
  • Correct Answer: Option B

the nature of the reactant effects the

the nature of the reactant effects the
  • A. nature of product
  • B. activation energy
  • C. rate of reaction
  • D. heat of the reaction
  • Correct Answer: Option C

Activation energy is the energy barrier for the formation of

Activation energy is the energy barrier for the formation of
  • A. activation complex
  • B. intermediates
  • C. reactants
  • D. products
  • Correct Answer: Option D

In the exothermic reactions, the products are at energy level

In the exothermic reactions, the products are at energy level
  • A. higher than reactant
  • B. lower than reactant
  • C. equal to reactants
  • D. away from reactants
  • Correct Answer: Option A

The rate constants of chemical reactions are strongly influenced by

The rate constants of chemical reactions are strongly influenced by
  • A. catalyst
  • B. temperature
  • C. nature and concentration of reactants
  • D. by all of them
  • Correct Answer: Option D

When the products are in lower energy state than the reactants, the reaction is

When the products are in lower energy state than the reactants, the reaction is
  • A. stable
  • B. endothermic
  • C. at equilibrium
  • D. exothermic
  • Correct Answer: Option D

Energy of activation is usually expressed in

Energy of activation is usually expressed in
  • A. joules
  • B. calories
  • C. ergs
  • D. newtons
  • Correct Answer: Option A

Activation energy has a symbol of

Activation energy has a symbol of
  • A. E0
  • B. Ea
  • C. E
  • D. ΔE
  • Correct Answer: Option B

The rate of reaction decrease if the temperature of the reaction system

The rate of reaction decrease if the temperature of the reaction system
  • A. is increased
  • B. kept constant
  • C. is decreased
  • D. is kept changing
  • Correct Answer: Option C

When molecules attain energy more than the average kinetic energy, they form

When molecules attain energy more than the average kinetic energy, they form
  • A. product
  • B. reactant
  • C. activated complex
  • D. biproduct
  • Correct Answer: Option C

For a chemical reaction the number of molecules that become activated per unit time is indicate by

For a chemical reaction the number of molecules that become activated per unit time is indicate by
  • A. velocity of molecules
  • B. velocity of reaction
  • C. kinetic energy
  • D. potential energy
  • Correct Answer: Option A

Once a reaction starts, heat released by activated complex provides heat to the remaining molecules for

Once a reaction starts, heat released by activated complex provides heat to the remaining molecules for
  • A. reaction
  • B. activated complex
  • C. product
  • D. reactant
  • Correct Answer: Option A

The value of the activation energy is much greater than average kinetic energy of the

The value of the activation energy is much greater than average kinetic energy of the
  • A. atoms
  • B. molecules
  • C. reactants
  • D. products
  • Correct Answer: Option B

The minimum amount of energy that a reaction system requires to attain transition state is called

The minimum amount of energy that a reaction system requires to attain transition state is called
  • A. internal energy
  • B. deactivation energy
  • C. deactivation
  • D. reaction energy
  • Correct Answer: Option B

Two molecules with sufficient energy collide to form

Two molecules with sufficient energy collide to form
  • A. reactant
  • B. product
  • C. activated complex
  • D. intermediate
  • Correct Answer: Option C
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