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Chemistry 15: 3-4

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Chemical Equilibrium Constants

Chapter 15: 3-4 Homework

Reading Preparation

Textbook assignment: Read Kotz and Triechel, Chemistry and Chemical Reactivity Chapter 15: Sections 3 and 4.

Kotz and Triechel, Chemistry and Chemical Reactivity Chapter 15: Sections 3-4.

Study Notes
  1. 15.3 We determine the equilibrium constant experimentally, by measuring the concentration of the products and reactants over time and determining when the reaction comes to equilibrium, then us the final concentrations to calculate the equilibrium constant. We create a table that identifies the initial concentrations, the amount of change, and the equilibrium concentrations.
  2. 15.4 Once the equilibrium constant has been calculated for one set of conditions, we can determine the final concentrations of a set of reactants for all other conditions, including overall concentrations when a reaction requires multiple steps. The method involves identifying initial and final concentrations, and the amount of change.

Key Formula

Equilibrium Constant Determinations
Components Reactants Products
Reaction Equation aA+ bB cC+ dD
Initial concentrations (Molarity) [A]  [B]  0  0
Change in concentration (Molarity) -ax  -bx  +cx  +dx
Equilibrium concentrations (Molarity) [A]-ax  [B]-bx  +cx  +dx
K =   [ C ] c [ D ] d [ A ] a [ B ] b

Web Lecture

Read the following weblecture before chat: Using the Equilibrium Constant

Study Activity

Videos for Chapter 15: Principles of Chemical Reactivity: Equilibria

Review the Videos at Thinkwell Video Lessons.

  • Under "Chemical Equilibrium"
    • Using Equilibrium Constants
      • Strategies for Solving Equilibrium Problems
      • Solving Problems far from Equilibrium
      • An Equilibrium Problem Using the Quadratic Equation

I haven't found a good simulation yet....

Chat Preparation Activities

Chapter Quiz

(Aligns to) AP #12 GUIDED INQUIRY — Determining the rate law — Phase I

Using the resources below, select a reaction and one of the methods developed in Lab #11 that you can use to determine the concentration of its reactants and products at periodic intervals. Identify the materials and equipment, and outline the procedure you will use to colect concentration data at set intervals.