A catalyst (A) Initiates a reaction (B) Lowers the activation energy of reacting molecules (C) Is capable of reacting with any one of the reactants (D) Cannot be recovered chemically unchanged at the end of a chemical reaction

A catalyst
(A) Initiates a reaction
(B) Lowers the activation energy of reacting molecules
(C) Is capable of reacting with any one of the reactants
(D) Cannot be recovered chemically unchanged at the end of a chemical
reaction
by

1 Answer

Answer :

(C) Is capable of reacting with any one of the reactants
by

Related questions

Pick out the correct statement. (A) In catalytic reactions, the catalyst reacts with the reactants (B) A catalyst initiates a chemical reaction (C) A catalyst lowers the activation energy of the reacting molecules (D) A catalyst cannot be recovered chemically unchanged at the end of the chemical reaction

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Last Answer : (C) A catalyst lowers the activation energy of the reacting molecules

For a heterogeneous catalytic reaction (A) Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction (B) A relatively small amount of catalyst can cause the conversion of large amount of reactants which does not mean that catalyst concentration is important (C) The catalyst does not form an intermediate complex with the reactant (D) The surface of the catalyst does not play an important role during reaction

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Last Answer : (A) Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction

Pick out the wrong statement. (A) A catalyst does not alter the final position of equilibrium in a reversible reaction (B) A catalyst initiates a reaction (C) A catalyst is specific in reaction (D) A catalyst remains unchanged in chemical composition at the end the reaction

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A catalyst in a chemical reaction (A) Decreases the activation energy (B) Alters the reaction mechanism (C) Increases the frequency of collisions of reacting species (D) All (A), (B) and (C)

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What happens when a catalyst is added to a system at equilibrium? A The reaction follows an alternative pathway of lower activation energy. B The heat of reaction decreases. C The potential energy of the reactants decreases. D The potential energy of the products decreases. E The rate of chemical reaction decreases.

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The difference between Threshold energy and average energy of the molecules is called activation energy. Ina chemical reaction lowers the rate of reaction the greater will be. The activation energy

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Burning of Gasoline initially requires heat before it burns spontaneously. Which of the following does not give a good explanation of this phenomenon?  a. the initial heat rises the enthalpy of the reactant  b. the initial heat lowers the activation of energy of the reactants  c. the enthalpy of reactants is lower than the enthalpy of products.  d. The enthalpy of the product is lower than the enthalpy of the reactant

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Photochemical reaction rate does not depend significantly on temperature, because (A) It is a reversible reaction (B) It is an exothermic reaction (C) The energy of reacting molecules exceeds the activation energy by absorption of light (D) None of these

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The increase in the rate of reaction with temperature is due to (A) Increase in the number of effective collisions (B) Decrease in activation energy (C) Increase in the average kinetic energy of the reacting molecules (D) None of these

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Rate of a chemical reaction is not influenced by the (A) Catalyst (B) Temperature (C) Reactants concentration (D) Number of molecules of reactants taking part in a reaction

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Promoter (A) Initiates a chemical reaction and is a catalyst by itself (B) Alters the position of equilibrium in a reversible reaction (C) Increases the number of active centres by increasing the unevenness of catalyst surface and by creating discontinuities in the crystals(D) All (A), (B) and (C)

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A catalyst remains unchanged at the end of the reaction with regard to (a) Quality (b) Chemical composition (c) Physical state (d) Quantity and chemical composition

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Which one of the following statements regarding a catalyst is not correct? A An enzyme is a catalyst that only binds certain substrates. B An enzyme is a protein that is a highly efficient catalyst for one or more chemical reactions in a living system. C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

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In a reaction, the threshold energy is equal to (where, A = activation energy N = normal energy of reactants) (A) A (B) N (C) A + N (D) A - N

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Threshold energy in a reaction is equal to the (A) Activation energy (B) Normal energy of reactants (C) Sum of (A) & (B) (D) Neither (A) nor (B)

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The energy of activation of a chemical reaction: (A) Is same as heat of reaction at constant pressure (B) Is the minimum energy which the molecules must have before the reaction can take place (C) Varies as fifth power of the temperature (D) Both (B) and (C)

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Pick out the correct statement. (A) A lower temperature favours the reaction of lower activation energy (B) The dispersion number for a reactor/vessel is uL/D (C) The rate controlling step in a reaction involving many steps is the fastest step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

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The reason why a catalyst increases the rate of reaction is that, it (A) Decreases the energy barrier for reaction (B) Increases the activation energy (C) Decreases the molecular collision diameter (D) None of these

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Pick out the wrong statement. (A) In a multistep reaction, the slowest step is the rate determining step (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature (C) Slow chemical reactions have generally high values of activation energy (D) Molecularity of a reaction cannot be zero but the order of a reaction can be zero

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What is the name for a chemical reaction that builds up larger molecules? a. dehydration synthesis b. hydrolysis c. reactants d. products

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What lowers activation energy in enzymes?

Description : What lowers activation energy in enzymes?

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The excess energy of the reactants required to dissociate into products is known as the __________ energy. (A) Thermal (B) Activation (C) Threshold (D) Binding

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What purpose does FeCl3 serve in the electrophilic aromatic substitution reaction between chlorine and benzene? (a) It serves as a radical initiator to produce the chlorine radical needed to propagate the chain reaction. (b) It functions by destabilizing the carbocationic intermediate and thereby increases the rate of H+ loss. (c) It serves as a Lewis base catalyst by reacting with Cl2 to generate chloride ions. (d) It serves as a Lewis acid catalyst by reacting with the Cl2 and thereby activates it toward attack by benzene’s π electrons.

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A catalyst is a substance which (a) Changes the equilibrium of a reaction so that the concentration of the product increases (b) Increases the rate of reaction and increases the equilibrium concentration of products (c) Hastens the attainment of equilibrium (d) Increases the activation energy

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A system of reacting substances from which neither the reactants nor the products are taken away or added to is called?

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A system of reacting substances from which neither the reactants nor the products are taken away or added to is called?

Description : A system of reacting substances from which neither the reactants nor the products are taken away or added to is called?

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The reaction rate almost gets doubled for 10°C rise in temperature. This is due to the fact that the (A) Increased temperature reduces the activation energy (B) Fraction of molecules having threshold energy increases (C) Collision frequency increases (D) Value of threshold energy decreases

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In an exothermic chemical reaction, the reactants compared to the products have (A) Higher temperature (B) More energy (C) Less energy (D) Same energy

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In autocatalytic reactions, (A) One of the reactants acts as a catalyst (B) One of the products acts as a catalyst (C) Catalysts have very high selectivity (D) No catalyst is used

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Half life period of a chemical reaction is (A) The time required to reduce the concentration of the reacting substance to half its initial value (B) Half of the space time of a reaction (C) Half of the residence time of a reaction (D) None of these

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"The rate at which a substance reacts is proportional to its active mass and the rate of a chemical reaction is proportional to the product of active masses of the reacting substances". This is the (A) Lewis-Randall rule (B) Statement of Van't Hoff Equation (C) Le-Chatelier's principle (D) None of these

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