Description : 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
Last Answer : (C) A + N
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 : The excess energy of the reactants required to dissociate into products is known as the __________ energy. (A) Thermal (B) Activation (C) Threshold (D) Binding
Last Answer : (B) Activation
Description : It is important to balance the chemical equations to satisfy the law of conservation of mass. Which of the following statements of the law is incorrect? (a) The total mass of the elements present in ... the reaction (d) Mass can neither be created nor can it be destroyed in a chemical Reaction.
Last Answer : Answer : (c) The chemical composition of the reactants is the same before and after the reaction
Description : 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 ... with the reactant (D) The surface of the catalyst does not play an important role during reaction
Last Answer : (A) Free energy of activation is lowered in the presence of catalyst, which remains unchanged at the end of reaction
Description : 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
Last Answer : (C) Is capable of reacting with any one of the reactants
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 : 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 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 ... molecules (D) A catalyst cannot be recovered chemically unchanged at the end of the chemical reaction
Last Answer : (C) A catalyst lowers the activation energy of the reacting molecules
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 : Pick out the correct statement. (A) A catalyst does not change AH of the reaction (B) A catalyst changes the equilibrium point (C) Law of mass action was suggested by Le-Chatelier (D) The difference between the energy of reactants and that of the products is the activation energy
Last Answer : (A) A catalyst does not change AH 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 : 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 : 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 : 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 : The first law of thermodynamics may be expressed in the following equivalent a. the net heat transfer id equal to the network b. the sum of the total energy forms leaving the system boundary is ... neither be created nor destroyed but only converted from one form to another d. all of the above
Last Answer : all of the above
Description : A system of reacting substances from which neither the reactants nor the products are taken away or added to is called?
Last Answer : Closed system
Description : 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 ... of products. d. The enthalpy of the product is lower than the enthalpy of the reactant
Last Answer : the enthalpy of reactants is lower than the enthalpy of products.
Description : With increase in temperature, the equilibrium __________ rises in case of endothermic reaction. (A) Constant (B) Conversion (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Conversion
Description : Chemical kinetics can predict the __________ of a chemical reaction. (A) Rate (B) Feasibility (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (A) Rate
Description : In a CSTR __________ varies with time. (A) Reaction rate (B) Concentration (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (D) Neither (A) nor (B)
Description : Reaction of calcium carbide with water produces a gas, which is used (A) As an illuminant (B) For metal cutting/welding (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) & (B)
Description : Heat load in a cooling tower (A) Means the amount of heat thrown away (KCal/hr.) by the cooling tower (B) Is equal to the number of kg, of water circulated times the cooling range (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : If the overall efficiency and Murphree plate efficiency are equal, then both the equilibrium and operating lines are: (A) Straight (B) Parallel (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : The standard state of a gas (at a given temperature) is the state in which fugacity is equal to (A) Unity (B) Activity (C) Both (A) & (B) (D) Neither (A) nor (B)
Description : A catalyst in a chemical reaction __________ free energy change in the reaction. (A) Increases (B) Decreases (C) Either (A) or (B); depends on the type of catalyst (D) Neither (A) nor (B)
Last Answer : (C) Either (A) or (B); depends on the type of catalyst
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 : If the pore diffusion controls in a catalytic reaction, the apparent activation energy Ea is equal to (A) The intrinsic activation energy E (B) (E + ED) where ED is activation due to diffusion (C) (E + ED)/2 (D) ED/2
Last Answer : (D) ED/2
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 : 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
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 : 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 : In any spontaneous process, the __________ free energy decreases. (A) Helmholtz (B) Gibbs (C) Both ‘a’ & ‘b’ (D) Neither 'a' nor 'b'
Last Answer : (C) Both ‘a’ & ‘b’
Description : For a constant volume process __________ by the system is used only to increase the internal energy. (A) Heat absorbed (B) Work done (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Work done
Description : The internal energy of an incompressible fluid depends upon its (A) Pressure (B) Temperature (C) Both (A) & (B) (D) Neither (A) nor (B)
Last Answer : (B) Temperature
Description : The order of a chemical reaction is (A) An experimentally determined quantity (B) Always equal to the total stoichiometric number of reactants (C) Never fractional (D) None of these
Last Answer : (A) An experimentally determined quantity
Description : Pick out the correct statement. (A) If an insoluble gas is passed through a volatile liquid placed in a perfectly insulated container, the temperature of the liquid will increase (B) A ... compound is defined as the heat of reaction leading to the formation of the compound from its reactants
Last Answer : (D) The heat of formation of a compound is defined as the heat of reaction leading to the formation of the compound from its reactants
Description : Pick out the wrong statement. (A) Wine, rum & Vodka are prepared by the formulation of fruit juice, sugar beet & rye respectively (B) Protein catalysts are called enzymes (C) The rate ... concentration of reactants at high concentration of enzymes (D) Total sugar content in molasses is about 10%
Last Answer : (D) Total sugar content in molasses is about 10%
Description : In a reversible chemical reaction (where, Δx = number of moles of products-number of moles of reactants) (A) Addition of inert gas favours the forward reaction, when Δx is positive (B) Pressure has no effect on equilibrium, when Δn = ... any value of Δx (+ ve, - ve) or zero) (D) All 'a', 'b' & 'c'
Last Answer : D) All 'a', 'b' & 'c'
Description : During photosynthesis, energy is absorbed by chlorophyll, therefore it is: (a) exothermic reaction (b) endothermic reaction (c) neither exothermic nor endothermic reaction (d) the process takes place in plants only
Last Answer : (b) endothermic reaction
Description : In an exothermic chemical reaction, the reactants compared to the products have (A) Higher temperature (B) More energy (C) Less energy (D) Same energy
Last Answer : (B) More energy
Description : For a solid catalysed chemical reaction, the effectiveness of solid catalyst depends upon the __________ adsorption. (A) Physical (B) Chemical (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (B) Chemical
Description : For multiple reactions, the flow pattern within the vessel affects the (A) Size requirement (B) Distribution of reaction products (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (C) Both (A) and (B)
Description : Multistage catalytic converter is not used in the (A) Conversion of SO2 to SO3 (B) NH3 synthesis reaction (C) Both (A) and (B) (D) Neither (A) nor (B)
Last Answer : (B) NH3 synthesis reaction
Description : In the reaction, represented by, 2SO2 + O2 ⇌ 2SO3; ΔH = - 42 kcal; the forward reaction will be favoured by (A) Low temperature (B) High pressure (C) Both (A) and (B) (D) Neither (A) nor (B)
Description : For the reversible exothermic reaction, N2 + 3H2 ⇌ 2NH3, increase of pressure would (A) Shift the equilibrium towards right (B) Give higher yield of NH3 (C) Both (B) and (C) (D) Neither (A) nor (B)
Last Answer : (C) Both (B) and (C)
Description : The internal energy of the combustion products is __________compared to that of reactants. (A) More (B) Less (C) Equal (D) More or less; (depends on the state of fuel.)
Last Answer : (B) Less
Description : A bolometer is (A) Used for the measurement of thermal radiation (B) An element which senses optical input and delivers thermal output (C) Both (A) & (B) (D) Neither (A) nor (B)