1. (a) Define molecularity and order of the reaction. (b) For an elementary reaction A + B Products, the reaction rate at 500 K is ten times that at 400 K. Calcu the activation energy for this reaction. [6+10 2. (a) (a) Define “Activation Energy” and write the equation to calculate it. b) A reaction has E = 400 kJ. By what percentage percentage does the reaction rate change if the temperature is raised from 300 K to 310 K, (b) from 2000 K to 2010 K [6+10 3. a) What is activation energy and discuss its temperature dependency. b) A 1100 K, n-nonane thermally cracks (breaks down into small molecules molecules 20 times as rapidly as at 1000K Find the activation energy for this decomposition [6+10 4. a) Differentiate between elementary and non-elementary reactions b) The pyrolysis of ethane proceeds with an activation activation energy of about 300kJ. How much faster is the decomposition at 650 °C than at 500 °C? [6+10 5. (a) The decomposition of nitrous oxide (N 2O) is found to be as follows: N2O N2 + 1/2O2, −rN2O = k1[N 2O]2 /(1+k 2[N2O]) What is the order of this reaction with respect to N 2O, and overall? (b) How can the kinetics of non-elementary reactions be explained? Briefly explain with suitable example. (c) What are the different types of intermediates formed in non -elementary reactions? Define each type. [4+
6. a) Define molecularity and order of the reaction b) A certain reaction has a rate given by – by – r r A = 0.005 (C A)2 mol/cm3 min. If the concentration is to be expres in mol/liter and time in hours what would be the value and units of the rate constant? 7. a) Define “Activation Energy” and write the equation to calculate it. b) Milk is pasteurized if it is heated to 63 °C for 30 min, but if it is heated to 74°C it only needs 15s for the result. Find the activation energy of this sterilization process
8. a) Differentiate between elementary and non-elementary reactions. b) A human being (75 kg) consumes about about 6000 kJ of food per day. Assume that the food is all glucose a the overall reaction is: C 6H12O6 + 6O2 6CO2 + 6H2O, -∆H -∆Hr = 2816kJ. Find man’s meta bolic rate in terms moles of oxygen used per m 3 of person per second. Assume density of man to be 1000kg/m 3 [6+ 9. a) Differentiate between elementary and non-elementary reaction b) For a gas reaction at 400K, the rate is reported as – as – dP dPA/ dT = 3.66 P A2 atm/hr. what are the units of rate constant? 10. (a) Come up with (guess and then verify) a mechanism that is consis tent with the experimentally found equation for the following reaction : 2A + B A2 B with + r A B = k [A] [B] ° (b) A common rule of temperature is that the rate of a reaction doubles for each 10 C rise in temperature. Justify? Read Free Foron 30this Days Sign up to vote title (c) Discuss briefly about the activation energy and temperature dependency. Useful Not useful
Master your semester with Scribd & The New York Times
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Special offer for11. students: Only $4.99/month. Experiment shows that the homogeneous decomposition of ozone proceeds with a rate, 2
-1
r = k[O3] [O]
What is the overall order of reaction? And suggest a two -step mechanism to explain this
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Finding the Orders of
1
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Cl2
2 Cl*
Cl* + CO
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Fast, at equilibrium COCl* Fast, at equilibrium
COCl* + Cl2
COCl2 + Cl Slow, rate controlling.
[16]
14. (a) For the reaction 2A+0.5 B C, write the relation between the rate of formation and disappearance o three components of the reaction. (b) A reaction has the stoichiometric equation 2A R+ S. What is the order of the reaction? [2] (c) The reaction with the following stoichiometric equation A+ 1/2 B R has the rate expression - r A =kC ACB0.5. What is the rate expression for the reaction written as 2A + B 2R [2] 2 3 (d) A certain reaction has a rate given by-r A =0.005CA , mol/cm .min. If the concentration is to be expresse mol/lit and time in hours, what would be the value and units of the reaction rate constant? [6] 15. For the non-elementary reaction A + 2B A+B
R
+ S if the mechanism suggested is :
R+X
B+X S where X is the unstable intermediate compound, (a) Derive an expression for rate of disappearance of A. (b) Explain how the rate constants can be evaluated using the rate law.
16. Consider the reaction A + 3B B+X
R
[8+8]
+ 3S for which the mechanism suggested is A + B
S +X
S+Y
B+Y R+S (a) Derive the rate law. You're Reading a Preview (b) Show how the rate law transforms when each of the mechanism steps controls the rate. [16] Unlock full access withoautfree 17. (a) What are the variables affecting the reaction rate. List thetrial. different forms of r eaction rate. (b) Derive the Arrhenius law from thermodynamic principles. (c) Experiment shows that the homogeneous decomposition ozone proceed with a rate −r 03 = K[O3]2[O Download With of Free Trial Suggest a two step mechanism to explain this rate and explain how would you further test this mechanism?
Problems:
18) a)Discuss the temperature dependency of the rate constant from Arrhenius law and also give Comparison of theories with this law.
Master your Scribd b) Givesemester the classificationswith of reactions. On doubling the concentration of 30 theDays reactant the rate Read Free For Sign up to vote on this title & The Newreaction Yorktriples. Times Useful Not useful Find the reaction order. Special offer for students: Only $4.99/month.
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19) a)Explain Arrhenius plot for temperature dependency of reaction rate and how do you find t
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experimentally observed rate is
2
-ro3 =k1[o3] [M]/[o2][M]+k2[o3] 21) a)How does the temperature dependency of reaction by Arrhenius law is adequate in comparison With the other expressions derived from theories. b) The decomposition nitrous oxide is found to proceed as follows: N2O →N2+1/2O2 2
-rN20 = k1[N2O] /1+K2[N2O] 22) a)Discuss temperature dependency of rate constant from Arrhenius law and also give
comparison Of theories with this law?
b)On doubling the concentration of the reactant the rate of the reaction triples.find the reaction o
23) a)Explain the salient features of theYou're three theories are proposed to explain the temperature Readingthat a Preview Unlock full access with a free trial.
dependence of reaction? 0
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b)A reaction is carried out at 40 c ,the activation energy of the reaction is 75kJ/mol .Find the temperature required to make the reaction twice faster . 24) Explain Arrhenius plot for temperature dependency of a reaction rate and how do you find the
activation energy Master your semester with Scribd Read Free Foron 30this Days Sign up to vote title variat b) Estimate the activation energy for oxidation of so2 to so3 over the vanadium catalyst if the & The New York Times Useful Not useful
Special offer forof students: Only reaction rate$4.99/month. constant with temperature as given below
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