2. Chemical Kinetics II Chemical Kinetics II +2 Chemistry power point presentation for unit 8 developed by syed saleem M.Sc.,M.Phil.,M.Ed.,PGDCA

3. Rate of reaction & Order of Reaction

4. Characteristics of order of reaction Magnitude of order of reaction may be zero or factional or integral Determined only by experiment Simple rxn possess low values of order like n=0,1,2. order > or = 3.0 is complex rxn Some rxn show fractional order Higher order rxn may be experimentally converted into simpler order by using excess of one or more reactants.

5. Rate Equation for First order Reaction Characteristics of first order reaction Examples of first order reactions Half life period

6. Pseudo first order reactions Determination of rate constant of acid catalysed hydrolysis of an ester

7. Temperature dependance of rate constant Arrhenius equation Arrhenius equation Threshold Energy Threshold Energy Activation Energy Activation Energy Energy of colloiding molecules Energy of colloiding molecules

8. Simple and Complex reactions Differentiate between simple and complex rxns

9. TYPES OF COMPLEX REACTIONS

10. 1. CONSECUTIVE REACTIONS 2. PARALLEL REACTIONS 2. PARALLEL REACTIONS 3. OPPOSING REACTIONS 3. OPPOSING REACTIONS

11. Assessment : one mark A. Choose the correct answer A. Choose the correct answer 1. The number of chloride ions that surrounds the central Na+ ion in NaCl 1. The number of chloride ions that surrounds the central Na+ ion in NaCl crystal is_______. crystal is_______. (a) 12 (b) 8 (c) 6 (d) 4 (a) 12 (b) 8 (c) 6 (d) 4 Ans c Ans c

12. 2. The Bragg’s equation is 2. The Bragg’s equation is (a) λ = 2d sinθ (a) λ = 2d sinθ (b) nd = 2λ sinθ (b) nd = 2λ sinθ (c) 2λ = nd sinθ (c) 2λ = nd sinθ (d) nλ = nd sinθ (d) nλ = nd sinθ Ans : d Ans : d

13. 3. A regular three dimensional arrangement of identical points in space is called (a) Unit cell (b) Space lattice (c) Primitive (d) Crystallography Ans : b

14. 4. The smallest repeating unit in space lattice which when repeated over and again results in the crystal of the given substance is called (a) Space lattice (b) Crystal lattice (c)Unit cell (d) Isomorphism ans :c

15. 5. The crystal structure of CsCl is (a) Simple cubic (b) face-centred cubic (c) Tetragonal (d) Body centred cubic Ans : d

16. 6. An example for Frenkel defect is (a) NaCl (b) AgBr (c) CsCl (d) FeS Ans : b Ans : b Practise listening from “ NOTHINGNESS “ Practise listening from “ NOTHINGNESS “ Do not judge things immediately Do not judge things immediately Tomorrow is mystery Tomorrow is mystery

17. 7. Semiconductors which exhibit conductivity due to the flow of excess negative electrons are called (a) Super conductors (b) n-type semiconductors (c) p-type semiconductors (d) Insulators Ans: b Ans: b

18. 8. In the Bragg’s equation for diffraction of X-rays,’n’ represents (a) The number of moles (b) Avogadro number (c) A quantum number (d) Order of reflection Ans : d

19. 9. The number of close neighbours in a body centred cubic lattice of identical spheres is (a) 6 (b) 4 (c) 12 (d) 8 (3) Promoting the right concept of education Ans : d

20. 10. The crystals which are good conductors of electricity and heat are (a) Ionic crystals (b) Molecular crystals (c) Metallic crystals (d) Covalent crystals ans : c ans : c

21. 11. In a simple cubic cell, each point on a corner is shared by (a) One unit cell (b) Two unit cell (c) 8 unit cell (d) 4 unit cell Ans : c Ans : c

22. 12. The ability of certain ultra cold substances to conduct electricity without resistance is called (a) Semiconductor (b) Conductor (c) Superconductor (d) Insulator Ans : c Ans : c

23. 13. The total number of atoms per unit cell in bcc is (a) 1 (b) 2 (c) 3 (d) 4 Ans : b

24. 14. Rutile is (a) TiO2 (b) Cu2O (c) MoS2 (d) Ru ans : a ans : a

25. 15. Semiconductors are used as (a) rectifiers (b) transistors (c) solar cells (d) all the above 15. Semiconductors are used as (a) rectifiers (b) transistors (c) solar cells (d) all the above ans : D ans : D

26. 16. An example of metal deficiency defect (a) NaCl (b) AgCl (c) CsCl (d) FeS Ans : d Ans : d

27. B. Answer in one or two sentences 17. Define the terms; space lattice and unit cell. 18. State Bragg’s law. 19. What are superconductors? 20. Sketch the (a) simple cubic (b) face-centred cubic and (c) body centred cubic lattices.

28. 21. How crystals are classified? 22. Give example for molecular and ionic crystals. 23. What is a vitreous state? 24. Give two example for AB and AB2 type ionic crystals.

29. 25. What is imperfection in solids? 26. What is coordination number? 27. Write a note on the assignment of atoms per unit cell in fcc. 28. Write a short note on metallic crystals. 29. How are glasses formed?

30. C. Answer not exceeding 60 words 30. What is Bragg’s equation? Give its significance. 31. Write the properties of ionic crystals. 32. Explain Schottky and Frenkel defects. 33. What is super conductivity? Give its uses. C. Answer not exceeding 60 words 30. What is Bragg’s equation? Give its significance. 31. Write the properties of ionic crystals. 32. Explain Schottky and Frenkel defects. 33. What is super conductivity? Give its uses.

31. 34. Explain AB and AB2 type ionic crystals with one example for each. 35. How Bragg’s equation is used for determining crystal structure. 36. Explain Bragg’s spectrometer method. 37. Explain the nature of glass.