11-5 RICE Problems And you. A common problem in chemistry is to mix several chemicals, allow them to reach equilibrium, and then calculate the final concentrations.

Slides:



Advertisements
Similar presentations
Chemical Equilibrium Unit 2.
Advertisements

Equilibrium Follow-up
1111 Chemistry 132 NT I never let my schooling get in the way of my education. Mark Twain.
Limiting Reactants. Limiting vs. Excess  Limiting Reactant-  Excess Reactant- The reactant in a chemical reaction that limits the amount of product.
Chemical Equilibrium Chapter 6 pages Reversible Reactions- most chemical reactions are reversible under the correct conditions.
Chemical Equilibrium Advanced Higher Chemistry Unit 2b.
Wednesday, April 9, 2008 Reminder – Lab Report Due Friday Homework – Reading Analysis (Sections Questions about Lab Section 17.2 Notes Section.
Chemical Equilibrium. Reversible Reactions A reaction that can occur in both the forward and reverse directions. Forward: N 2 (g) + 3H 2 (g)  2NH 3 (g)
1 Chemical Equilibrium Chapter 13 AP CHEMISTRY. 2 Chemical Equilibrium  The state where the concentrations of all reactants and products remain constant.
Copyright©2000 by Houghton Mifflin Company. All rights reserved. 1 Figure 13.1 A Molecular Representation of the Reaction 2NO 2 (g)      g) Over.
Equilibrium Law. Introduction to the Equilibrium law 2H 2 (g) + O 2 (g)  2H 2 O (g) Step 1:Set up the “equilibrium law” equation Kc = Step 2:Product.
Applications of Equilibrium Constants. Example For the reaction below 2A + 3B  2C A 1.5L container is initially charged with 2.3 mole of A and 3.0 mole.
5.2 - EQUILIBRIUM CONSTANT: K EQ Unit 5: Equilibrium.
Chemical Equilibrium Chapter 13.
Chapter 15: Chemical Equilibria. Manipulating Equilibrium Expressions : N 2 (g) + 3 H 2 (g)  2 NH 3 (g) K = =5.5 x 10 5 Reversing Reactions Multiplying.
Chapter 13 Chemical Equilibrium. Copyright © Houghton Mifflin Company. All rights reserved.13–2 Figure 13.1: A molecular representation of the reaction.
Sample Exercise 15.7 Calculating K When All Equilibrium Concentrations Are Known After a mixture of hydrogen and nitrogen gases in a reaction vessel is.
Buffers AP Chemistry.
Chemistry Chapter 12 – Quantitative Equilibrium Teacher: H. Michael Hayes.
Aim: Using mole ratios in balanced chemical equations.
EQUILIBRIUM BASICS Chapter Lesson Objectives Know -Factors that affect/don’t affect a reaction reaching equilibrium -K is equilibrium constant.
INTRODUCTION TO SOLUTIONS/ACIDS AND BASES HONORS CHEMISTRY MAY 27 TH, 2014.
Suppose human’s memory decays exponentially as a first order reaction and the half life is one day. Three days have passed since you came to class last.
Colorimetric Analysis & Determination of the Equilibrium for a Chemical reaction Help Notes AP Chemistry.
Buffers 1986 A.
1111 Chemistry 132 NT Be true to your work, your word, and your friend. Henry David Thoreau.
Chemical Equilibrium The state where the concentrations of all reactants and products remain constant with time. On the molecular level, there is frantic.
17.2 The equilibrium law Solve homogeneous equilibrium problems using the expression for Kc. –The use of quadratic equations will NOT be assessed.
Equilibrium: A State of Dynamic Balance Chapter 18.1.
Equilibrium. This is usually Question #1 on FR write equilibrium expressions convert between K P and K c eq. constants calculate eq. constants calculate.
Chapter 16 Equilibrium. How do chemical reactions occur? Collision Model Molecules react by colliding into one another. – This explains why reactions.
Predicting Equilibrium QCQC. Determine the reaction quotient for a system. Determine if a system is at equilibrium and, if not, which reaction is favoured.
Predicting Equilibrium. Determine the reaction quotient, Q, for a system. Include: stating the direction the reaction is proceeding towards equilibrium.
Equilibrium Systems and Stress
The Extent of a Reaction The tendency for a reaction to occur is indicated by the magnitude of the equilibrium constant. A value of K larger than 1 means.
1 Equilibrium Constant even though the concentrations of reactants and products are not equal at equilibrium, there is a relationship between them the.
Molarity Molarity is defined as the amount of moles of a compound dissolved in an amount of solvent (usually water). It can be solved with the equation:
Chapter 13 Equilibrium Dr. Walker DE Chemistry.
PROBLEM: The equilibrium constant for the butane < - - > isobutane isomerization reaction is 2.5 at 25°C. If 1.75 mol of butane and 1.25 mol of isobutane.
Chapter 9 Chemical Equilibrium
CHEMICAL EQUILIBRIUM.
10.3 Equilibrium Constants
or How Chemical Reactions Occur
Rate Laws Chemical reactions are reversible. 2NO2(g) → 2NO(g) + O2(g)
Using Equilibrium Constants
Section 19.3 Free Energy, the Reaction Quotient and the Equilibrium Constant Bill Vining SUNY College at Oneonta.
Week 5. Buffers solutions
CHEMICAL EQUILIBRIUM.
Solving Equilibrium Problems
Solving Equilibrium Problems
Chemical Equilibrium The state where the concentrations of all reactants and products remain constant with time. On the molecular level, there is frantic.
Sample Problem 10.1 Factors That Affect the Rate of Reaction
10.4 Using Equilibrium Constants
Topics 7 & 17: Chemical Equilibrium
Chapter 13 Reaction Rates and Chemical Equilibrium
Unit 2, Lesson 10: Equilibrium Calculations – Part II
Chemical Equilibrium.
Limiting Reactants ABClark-Grubb.
Equilibrium.
Reaction Rates and Equilibrium
Chemical Equilibrium.
Equilibrium Station Review
Chemistry 30: equilibrium Part 3
Chapter 12 Chemical Kinetics Speed Steps
Chemical Equilibrium AP Chemistry, LFHS.
EQUILIBRIUM LAW.
14.9 Le Châtelier’s Principle: How a System at Equilibrium Responds to Disturbance Check out this graph of the concentration versus time for the reaction.
Copyright©2000 by Houghton Mifflin Company. All rights reserved.
Shifting Equilibrium.
Presentation transcript:

11-5 RICE Problems And you

A common problem in chemistry is to mix several chemicals, allow them to reach equilibrium, and then calculate the final concentrations. The steps involved in calculating the equilibrium concentrations are affectionately termed “RICE”. To illustrate the process, here’s an example:

: A mixture of M NO, M H 2, M H 2 O was allowed to reach equilibrium (initially there was no N 2 ). At equilibrium, the concentration of NO was found to be M. Determine the value of the equilibrium constant, K c, for the reaction: Step 1: Write the Reaction “R” 2 NO(g) + 2 H 2 (g) ↔ N 2 (g) + 2 H 2 O(g)

Step 2: Create an chart with initial concentrations “I”, the change in concentrations “C”, and the concentrations at equilibrium “E”. R:2 NO 2 H 2 N 2 2 H 2 O I: C: E: Note how we have assigned the change in the concentration (x) based on the appearance (+) of nitrogen, since its mole coefficient is 1. The concentration of the reactants will then decrease (-) by 2x and the water will increase (+) by 2x. +X+2X-2X

R:2 NO 2 H 2 N 2 2 H 2 O I: C:-2x -2x +x +2x E: The change in [NO] was – 2x = x = x =0.019

R:2 NO 2 H 2 N 2 2 H 2 O I: C:-2x -2x +x +2x E: x =0.019 We can now calculate the remaining “E” values: H 2 = – = 0.012M N 2 = 0.019M H 2 O = = 0.138M 0.012M0.019M 0.138M

2 NO 2 H 2 N 2 2 H 2 O 0.062M 0.012M 0.019M 0.138M Solving for K c [N 2 ][H 2 O] 2 [NO] 2 [H 2 ] 2 = (0.019)(0.138) 2 (0.062) 2 (0.012) 2 = 650 or 6.5 x 10 2

Cool huh! I have posted an additional powerpoint that walks through the steps sequentially if you need added examples to follow.