c6_eq03 - Chapter 6 Chemical Equilibrium 6-1 The...

Info iconThis preview shows pages 1–13. Sign up to view the full content.

View Full Document Right Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon

Info iconThis preview has intentionally blurred sections. Sign up to view the full version.

View Full DocumentRight Arrow Icon
This is the end of the preview. Sign up to access the rest of the document.

Unformatted text preview: Chapter 6 Chemical Equilibrium 6-1 The Equilibrium Constant 1. Concentrations of solutes should be expressed as moles per liter . 2. Concentrations of gases should be expressed in bars. 3. Concentrations of pure solids, pure liquids, and solvents are omitted because they are unity. Equilibrium: State in which the forward and reverse rates of all reactions are equal, so the concentrations of all species remain constant. 6-1 The Equilibrium Constant 6-4. Write the expression for the equilibrium constant for each of the following reactions. Write the pressure of a gaseous molecule, X, as P X . If a reaction is reversed, then K = 1/ K NH 3 (aq)+H 2 O NH 4 + +OH- NH 3 (aq)+H 2 O NH 4 + +OH- K b =1.76 10-5 Ka=? If two reactions are added, then K 3 = K 1 K 2 . 6-6. From the equations find the value of K for the reaction HOBr H + + OBr . All species are aqueous . 6-2 Equilibrium and Thermodynamics Gibbs free energy: G Systems at constant temperature and pressure , which are common laboratory conditions, have a tendency toward lower enthalpy and higher entropy . A chemical reaction is driven toward the formation of products by a negative value of H (heat given off) or a positive value of S (more disorder) or both. When H is negative and S is positive, the reaction is clearly favored. When H is positive and S is negative, the reaction is clearly disfavored. Equilibrium and Thermodynamics G = H - T S G = G o + RT ln (K) at equilibrium G = 0; thus G o = - RT ln (K) Equilibrium and Thermodynamics Le Chatelier's Principle If a stress, such as a change in concentration, pressure, temperature, etc., is applied to a system at equilibrium, the equilibrium will shift in such a way as to lessen the effect of the stress. Q => reaction quotient To quantitatively precipitate chloride by AgNO 3 , what measure should be taken? Ag + +Cl- AgCl(s) If Q = K , the system is at equilibrium. If Q > K , there is too much product and the equilibrium shifts to the left. If Q < K , there is too much reactant, and the equilibrium shifts to the right. Predicting the Direction of Approach to Equilibrium...
View Full Document

Page1 / 55

c6_eq03 - Chapter 6 Chemical Equilibrium 6-1 The...

This preview shows document pages 1 - 13. Sign up to view the full document.

View Full Document Right Arrow Icon
Ask a homework question - tutors are online