1 / 16

First Order Reactions

Rate Laws Concentration [time]. First Order Reactions Goal: convert rate law into a convenient equation to give concentrations as a function of time. For a first order reaction, the rate doubles as the concentration of a reactant doubles. Rate Laws Concentration [time].

naoko
Télécharger la présentation

First Order Reactions

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. Rate Laws Concentration [time] • First Order Reactions • Goal: convert rate law into a convenient equation to give concentrations as a function of time. • For a first order reaction, the rate doubles as the concentration of a reactant doubles.

  2. Rate Laws Concentration [time] • First Order Reactions • A plot of ln[A]t versus t is a straight line with slope -k and intercept ln[A]0. • In the above we use the natural logarithm, ln, which is log to the base e.

  3. Rate Laws Concentration [time] • First Order Reactions

  4. Rate Laws Concentration [time] • Second Order Reactions • For a second order reaction with just one reactant • A plot of 1/[A]t versus t is a straight line with slope k and intercept 1/[A]0 • For a second order reaction, a plot of ln[A]tvs. t is not linear.

  5. Rate Laws Concentration [time] Second Order Reactions

  6. Rate Laws Concentration [time] • Half-Life • Half-life is the time taken for the concentration of a reactant to drop to half its original value. • For a FIRST ORDER process, half life, t½ is the time taken for [A]0 to reach ½[A]0. • Mathematically,

  7. Rate Laws Concentration [time] • Half-Life • For a SECOND ORDER half-life depends in the initial concentration:

  8. Rate Laws Concentration [time] • First Order Reactions • Goal: convert rate law into a convenient equation to give concentrations as a function of time. • For a first order reaction, the rate doubles as the concentration of a reactant doubles.

  9. Rate Laws Concentration [time] • First Order Reactions • A plot of ln[A]t versus t is a straight line with slope -k and intercept ln[A]0. • In the above we use the natural logarithm, ln, which is log to the base e.

  10. Rate Laws Concentration [time] • First Order Reactions

  11. Rate Laws Concentration [time] • Second Order Reactions • For a second order reaction with just one reactant • A plot of 1/[A]t versus t is a straight line with slope k and intercept 1/[A]0 • For a second order reaction, a plot of ln[A]tvs. t is not linear.

  12. Rate Laws Concentration [time] Second Order Reactions

  13. Rate Laws Concentration [time] • Half-Life • Half-life is the time taken for the concentration of a reactant to drop to half its original value. • For a FIRST ORDER process, half life, t½ is the time taken for [A]0 to reach ½[A]0. • Mathematically,

  14. Rate Laws Concentration [time] • Half-Life • For a SECOND ORDER half-life depends in the initial concentration:

More Related