Arrhenius equation shows the variation of __________ with
temperature.
(A) Reaction rate
(B) Rate constant
(C) Energy of activation
(D) Frequency factor

1 Answer

Answer :

(B) Rate constant

Related questions

Description : Arrhenius equation represents graphically the variation between the __________ and temperature. (A) Rate of reaction (B) Frequency factor (C) Rate constant (D) Activation energy

Last Answer : (C) Rate constant

Description : The unit of frequency factor in Arrhenius equation is (A) Same as that of rate constant (B) Same as that of activation energy (C) Dimensionless (D) None of these

Last Answer : (A) Same as that of rate constant

Description : The units of frequency factor in Arrhenius equation (A) Are the same as those of the rate constant (B) Depend on the order of the reaction (C) Depend on temperature, pressure etc. of the reaction (D) Are cycles per unit time

Last Answer : (A) Are the same as those of the rate constant

Description : With increase in temperature, the rate constant obeying Arrhenius equation (A) Increases (B) Decreases (C) Decreases exponentially (D) Can either increase or decrease; depends on the frequency factor

Last Answer : (C) Decreases exponentially

Description : Pick out the wrong statement. (A) A particular chemical reaction is more temperature sensitive at low temperatures (B) A very high value of equilibrium constant, K (K >> 1) indicates that the ... ) Non-ideal flow takes place in reactors due to recycling, channeling or by creation of stagnant regions

Last Answer : (C) The intercept of the Arrhenius plot is called the 'activation energy

Description : At a given value of E/R (ratio of activation energy and gas constant), the ratio of the rate constants at 500°K and 400°K is 2, if Arrhenius law is used. What will be this ratio, if transition state theory is used with the same value of ‘E/R’? (A) 1.6 (B) 2 (C) 2.24 (D) 2.5

Last Answer : (D) 2.5

Description : According to Arrhenius equation of temperature dependency of rate constant for an elementary reaction (A) k ∝ √T (B) k ∝ e -E/RT (C) k ∝ T e -E/RT (D) None of these

Last Answer : (B) k ∝ e -E/RT

Description : Pick out the wrong statement. (A) Use of different catalysts in a reversible catalytic chemical reaction does not change the equilibrium composition (B) Alumina is added as a promoter to ... Arrhenius plot (D) Presence of inerts affects the equilibrium conversion of reactants in a chemical reaction

Last Answer : (C) Activation energy for a reaction is obtained from the intercept of the Arrhenius plot

Description : 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

Last Answer : (B) Fraction of molecules having threshold energy increases

Description : If the rate of a chemical reaction becomes slower at a given temperature, then the (A) Initial concentration of the reactants remains constant (B) Free energy of activation is lower (C) Entropy changes (D) Free energy of activation is higher

Last Answer : (D) Free energy of activation is higher

Description : Arrhenius equation K = Ae-E a / R T In some reactions, Rate of reaction is directly proportional to. Concentration of catalyst Catalyst used in Bio-Chemical reactions is called. Enzymes Reactions catalyzed by light are called as. Photo catalyzed or Photosensitised reactions

Last Answer : Define order of reaction

Description : An increase in which of the following results in a decrease in the rate of the chemical reaction? (a) temperature (b) concentration (c) collision frequency (d) energy of activation

Last Answer : energy of activation

Description : The rate expression for a heterogeneous catalytic reaction is given by, - rA = K.KA PA(1 + KA.PA + KR.PR), where K is surface reaction rate constant and KA and KR are absorption equilibrium constants of A and R respectively. If KR PR ... R and A) (A) E (B) E + ΔHA (C) E + ΔHA - ΔHR ) (D) ΔHA + ΔHR

Last Answer : (C) E + ΔHA - ΔHR )

Description : Pick out the wrong statement. (A) Visible radiation provides the necessary activation energy in photochemical reactions (B) The order and molecularity of a complex reaction may not be the same (C) For ... rate constant (k) (D) Molecularity of the reaction is always a whole number greater than zero

Last Answer : (B) The order and molecularity of a complex reaction may not be the same

Description : The variation of heat of reaction with temperature at constant pressure is given by the __________ law. (A) Kelvin's (B) Antoine’s (C) Kirchoff’s (D) None of these

Last Answer : (C) Kirchoff’s

Description : 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)

Last Answer : (B) Is the minimum energy which the molecules must have before the reaction can take place

Description : he quantitative effect of temperature on chemical equilibrium is given by the (A) Van’t-Hoff equation (B) Le-Chatelier's principle (C) Arrhenius equation (D) None of these

Last Answer : (A) Van’t-Hoff equation

Description : Enzymes increases the rate of reactions by (A) Increasing the free energy of activation (B) Decreasing the energy of activation (C) Changing the equilibrium constant of the reaction (D) Increasing the free energy change of the reaction

Last Answer : Answer : B

Description : Enzymes accelerate the rate of reactions by (A) Increasing the equilibrium constant of reactions (B) Increasing the energy of activation (C) Decreasing the energy of activation (D) Decreasing the free energy change of the reaction

Last Answer : Answer : C

Description : 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 ... increasing the activation energy. D Catalysts do not alter the equilibrium constant for a chemical reaction.

Last Answer : C Catalysts increase the rate of a reaction by altering the mechanism, thereby increasing the activation energy.

Description : 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 ... step (D) Pore volume and porosity of a catalyst is measured by Brunauer￾Emmett-Teller (BET) technique

Last Answer : (A) A lower temperature favours the reaction of lower activation energy

Description : 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 ... energy (D) Molecularity of a reaction cannot be zero but the order of a reaction can be zero

Last Answer : (B) In general, the rate of a reaction becomes triple for every 10°C rise in temperature

Description : 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

Last Answer : (C) The energy of reacting molecules exceeds the activation energy by absorption of light

Description : 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

Last Answer : (B) Decrease in activation energy

Description : Higher free energy of activation of a chemical reaction (at a given temperature) implies (A) Slower rate of reaction (B) Higher rate of reaction (C) Higher equilibrium conversion (D) Both (B) and (C)

Last Answer : (A) Slower rate of reaction

Description : Variation of equilibrium pressure with temperature for any two phases of a given substances is given by the __________ equation. (A) Gibbs-Duhem (B) Maxwell's (C) Clapeyron (D) None of these

Last Answer : (C) Clapeyron

Description : The reaction step that has its transition state at the highest point on the reaction coordinate is the called the __________. (a) rate-determining step (b) activation energy (c) transition step (d) product favored step

Last Answer : rate-determining step

Description : 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)

Last Answer : (D) All (A), (B) and (C)

Description : The role of a catalyst in a chemical reaction is to change the (A) Equilibrium constant (B) Activation energy (C) Final products (D) Heat of reaction

Last Answer : (B) Activation energy

Description : Catalytic action in a catalytic chemical reaction follows from the ability of catalyst to change the (A) Activation energy (B) Equilibrium constant (C) Heat of reaction (D) None of these

Last Answer : (A) Activation energy

Description : The catalyst in a first order chemical reaction changes the (A) Equilibrium constant (B) Activation energy (C) Heat of formation of the product (D) Heat of reaction

Last Answer : (B) Activation energy

Description : When the wavelength of incident X-rays increases, the angle of diffraction (A) Decreases (B) Increases (C) Remain constant (D) Shows no systematic variation

Last Answer : Option A

Description : When the reaction occurs in the diffusion controlled region, the apparent activation energy as measured is only __________ the true value. (A) Twice (B) Half (C) Equal (D) None of these

Last Answer : (B) Half

Description : The excess energy of reactants in a chemical reaction required to dissociate into products is termed as the __________ energy. (A) Activation (B) Potential (C) Binding (D) Threshold

Last Answer : (A) Activation

Description : A chemical reaction occurs when the energy of the reacting molecules is __________ the activation energy of the reaction. (A) Less than (B) Equal to (C) More than (D) Equal to or more than

Last Answer : (D) Equal to or more than

Description : A chemical reaction occurs, when the energy of the reacting molecules is __________ the activation energy of reaction. (A) Less than (B) Equal to (C) More than (D) Equal to or more than

Last Answer : (D) Equal to or more than

Description : 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

Last Answer : (A) Decreases the energy barrier for reaction

Description : Enzymes increase the rates of reactions by (A) Increasing the free energy of activation (B) Decreasing the energy of activation (C) Changing the equilibrium constant of the reaction (D) Increasing the free energy change of the reaction

Last Answer : Answer : B

Description : Pick out the correct statement. (A) Reactions with high activation energies are very temperature sensitive (B) Chemical equilibrium is a static state (C) A photochemical reaction is catalysed by ... occurs when the energy of the reacting molecule is less than the activation energy of the reaction

Last Answer : (A) Reactions with high activation energies are very temperature sensitive (B) Chemical equilibrium is a static state

Description : Pick out the wrong statement: (A) Chemical reactions with high activation energy are very temperature sensitive (B) A flat velocity profile exists in a plug flow reactor (C) The residence ... D) Half life of a reaction increases with increased initial concentration for reaction orders more than one

Last Answer : (C) The residence time for all the elements of fluid in case of a P.F.R. need not be same

Description : Pick out the wrong statement. (A) Exit age description function (E) and internal age distribution function (I) are related as, E = -(dI/dθ) (B) Chemisorption studies are useful in the ... energy (D) A catalyst increases the potential energy barrier over which the reactants must pass to form products

Last Answer : (D) A catalyst increases the potential energy barrier over which the reactants must pass to form products

Description : Pick out the wrong statement. (A) Catalytic activity of enzyme catalysed reactions which is affected by temperature, pH value & chemical agents, is maximum at a temperature of about 45°C ... in enzyme catalysed reactions can be calculated by using the thermodynamic properties of substrates & prod

Last Answer : (C) Enzymes help in increasing the activation energy of the reaction

Description : The minimum energy required to allow a chemical reaction to proceed is termed as the 'threshold energy '. Chemical reactions with low activation energy are: (A) Always irreversible (B) Insensitive to temperature changes (C) Mostly irreversible (D) Highly temperature sensitive

Last Answer : (B) Insensitive to temperature changes

Description : . A batch reactor is characterised by (A) Constant residence time (B) Variation in extent of reaction and properties of the reaction mixture with time (C) Variation in reactor volume (D) Very low conversion

Last Answer : (B) Variation in extent of reaction and properties of the reaction mixture with time

Description : 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

Last Answer : How do you define the molecularity of a reaction ?

Description : 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

Last Answer : Ans:(c)

Description : Which of the following is incorrect about heterogeneous catalysis? a. The most effective catalysts are those which have small surface area b. Seperation of catlyst is easy c. Increase in the rate of reaction is due to decrease in the activation energy d. It is based upon the phenomenon of adsorption

Last Answer : a. The most effective catalysts are those which have small surface area

Description : 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 ... decreases. D The potential energy of the products decreases. E The rate of chemical reaction decreases.

Last Answer : A The reaction follows an alternative pathway of lower activation energy.

Description : One of the following is a possible cause of an abrupt frequency variation in a self exited transmitter oscillator circuits resulting to a poor frequency stability to hold a constant frequency ... capacitor in the oscillator D. Loose connections in the oscillator, amplifier, or antenna circuits.

Last Answer : D. Loose connections in the oscillator, amplifier, or antenna circuits.