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This slide completely describes you about the stuff include in it and also everything about chemical engineering. Fluid Mechanics. Thermodynamics. Mass Transfer Chemical Engineering. Energy Engineering, Mass Transfer 2, Heat Transfer,

1. Molecularity, rate and order of reaction

2. CONTENT Rate Reaction rate Factors effecting the rates Molecularity Order of reaction Note References

3. RATE Change in concentration of a reactant or product per unit time A B

4. Reaction rate Rate at which a specie losses its chemical identity, at particular volume per unit time.

5. Factors effecting rate Nature of the reactants State of subdivision/surface area Concentration Temperature Catalysts

6. Molecularity The number of ions or atoms or molecules involve in the rate determining step or rate limiting step is called molecularity . The molecularity will be only whole number and never be zero or fraction. Unimolecular Bimolecular Termolecular

7. Order of a reaction The sum of the powers of concentration terms in rate equation is known as order of reaction. (or) Order of reaction may be given with respect to all participating reactants in which case it is called order of reaction

8. p ro d uct Consider a reaction mA + nB Rate eq (R)=k[A] m [B] n Order = m + n

9. Zero Order Reaction When the reaction rate is independent of concentration of the reacting substance, it depends on the zero power of the reactant and therefore is zero order reaction. 4

10. First order Re a ction First order reaction consists of one reactant. A p r o d uct R = k[A] 1

11. Examples of first order reaction Thermal decomposition of N 2 O 5 N 2 O 5 N 2 O 3 +O 2 Hydrolysis of hydrogen peroxide H 2 O 2 H 2 O +1/2O 2 Decomposition of Calcium carbide CaCo 3 Cao + Co 2

12. Second Order Of Rea c tion Second order reaction consists of two reactants. 2A pro d u c ts products A+B Rate = Rate = k[A] 2 ; n=2 k[A] [B] ; n=1+1=2

13. Examples Of Second Order Reaction Thermal decomposition of Nitrous oxide 2N 2 O 2N 2 +o 2 Decomposition of NO 2 2NO 2 2NO +O 2 Decomposition of Hydrogen Iodide 2HI H 2 + I 2

14. Third Order Reaction Third order reaction includes three reactants 3A P r o d ucts r = k [A] 3 A+ B +C P r o d ucts r = k [A] [B] [C] 2A+B P r o d ucts r = k [A] 2 [B]

15. Examples Of Third Order Reaction 2NO + O 2 2NO + Cl 2 2FeCl 3 + SnCl 2 2NO 2 2NOCl 2FeCl 2 + SnCl 4

16. Note Molecularity is a theoretical concept Molecularity can not be zero, -ve, fractional, infinite and imaginary. Molecularity can not be grater than three because more than three molecules may not mutually collide with each other.

17. References: https://www.slideshare.net/PrawinDdy/difference-between-order-and-molecularity-of-a-reaction-2310?qid=738df5d0-0b7f-447b-8813-f8308ade64dd&v=&b=& from_search=1 https:// www.slideshare.net/Kamyaparashar/chemical-kinetics-presentation?from_action=save

18. THENKIEUU