1 / 14

Section 16-1

Expressing Reaction Rates. The reaction rate of a chemical reaction is stated as the change in concentration of a reactant or product per unit of time. Section 16-1. Expressing Reaction Rates (cont.). Reaction rates are determined experimentally. Section 16-1. Reaction Rates:.

aisha
Télécharger la présentation

Section 16-1

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Expressing Reaction Rates • The reaction rateof a chemical reaction is stated as the change in concentration of a reactant or product per unit of time. Section 16-1

  2. Expressing Reaction Rates (cont.) • Reaction rates are determined experimentally. Section 16-1

  3. Reaction Rates: 2NO2(g)  2NO(g) + O2(g) 1. Can measure disappearance of reactants 2. Can measure appearance of products 3. Are proportional stoichiometrically

  4. Section 16.1 A Model for Reaction Rates (cont.) Collision theory is the key to understanding why some reactions are faster than others. Section 16-1

  5. Collision Model Key Idea: Molecules must collide to react. However, only a small fraction of collisions produces a reaction. Why?

  6. Collision Model Collisions must have sufficient energyto produce the reaction (must equal or exceed the activation energy). Colliding particles must be correctly orientedto one another in order to produce a reaction.

  7. Collision Theory (cont.) • An activated complex is a temporary, unstable arrangement of atoms in which old bonds are breaking and new bonds are forming. Section 16-1

  8. Activation Energy The minimum energy required to transform reactants into the activated complex (The minimum energy required to produce an effective collision) Flame, spark, high temperature, radiation are all sources of activation energy

  9. Collision Theory (cont.) • High activation energy means that few collisions have the required energy and the reaction rate is slow. Section 16-1

  10. Collision Theory (cont.) Section 16-1

  11. Collision Theory (cont.) Section 16-1

  12. Collision Theory (cont.) Section 16-1

  13. A B C D Section 16.1 Assessment Which of the following is NOT a requirement for a reaction to occur, according to the collision theory? A.Reacting substances must collide. B.Reacting substances must be in an exothermic reaction. C.Reacting substances must collide in the correct orientation. D.Reacting substances must collide with sufficient energy to form an activated complex. Section 16-1

  14. A B C D Section 16.1 Assessment A temporary, unstable arrangement of atoms in which old bonds are breaking and new bonds are forming is called ____. A.reaction complex B.reaction substrate C.activated complex D.activated molecule Section 16-1

More Related