top-rated free essay

# Equilibrium and Acid Base Review

By thepwner Mar 11, 2014 518 Words
﻿ Equilibrium and Acid Base Test Review:May 2012
Things to know:
1. Explain DYNAMIC EQUILIBRIUM. Why does a reaction at equilibrium look like it is NOT reacting? 2. Are all reactions equilibrium reactions? What assumptions do we make when we say that a reaction does NOT take place or that it is UNIDIRECTIONAL and goes 100% to completion 3. Be able to sketch a graph of the following (assuming that you start with all reactants and no products) : a. A reaction that really doesn’t do anything

b. A reaction that seems to go to completion (Unidirectional) c. A reaction that favours the forward direction of the reaction d. A reaction that seems to have an equal balance of reactants and products at equilibrium e. A reaction that favours the reverse direction of the reaction 4. What does a K value represent for an equilibrium reaction? Write the generic equation for K 5. Match the following K values to the graphs that you created in question 3: a. Keq = very large

b. Keq = 1.0 (approx.)
c. Keq = 5.0 x 10-12
d. Keq = 3.5 x 102
e. Keq = very small
6. Outline Le Chatalier’s principles of equilibrium with respect to addition or removal of reactants and products, change in temperature for exo and endothermic reactions, and change in pressure where gases are involved in the reaction. 7. Why does the addition of a catalyst not alter the equilibrium? What does it do? 8. Does the addition of spectator ions or inert gases alter the equilibrium? 9. Be able to write the Keq expression for an equilibrium reaction. REMEMBER: the coefficients from the balanced equation become the exponents! 10. Be able to construct an ICE table to find equilibrium concentrations! 11. Given a Keq expression, be able to write the balanced equation! 12. Be able to match the column with definitions for the following terms: a. Keq, Ka, Kb

b. Acid, Base
c. Neutral
d. Weak acid, weak Base
e. pH, pOH
f. Strong Acid, Strong Base
g. Buffer solution
13. Be able to write out the equilibrium that takes place in a simple beaker of water. What is the Kw expression? pKw = 14! Why is this really helpful? 14. Be able to draw a diagram of hydronium ion. Why does this structure form spontaneously? 15. Be able to label Acid, Base, Conjugate Acid, Conjugate Base for an acid/base equilibrium 16. Be able to convert from pH/ H3O+ to pOH/ OH- for a strong acid or base 17. Be able to find pH for a weak acid using an ICE table and the Ka equation (and Ka value) 18. Be able to find pH (or pOH) for a weak base using ICE table and the Kb equation (and Kb value) 19. Be able to convert from pH/ H3O+ to pOH/ OH- for a weak acid or base 20. Be able to COMPARE relative pH values for acids or bases with the SAME concentration but differing Ka or Kb values 21. What is a buffer? How do buffers work? Be able to PLUG-and –SOLVE for a simple buffer question!

Sample Questions: See assigned homework questions for this unit, plus hand-outs and power points available on the classes web page!

Review session TUESDAY at lunch next week!

## Related Documents

• ###### Acids and Bases

...﻿ACIDS AND BASES The reason that acid-base reactions are so important is that many of the things you come into contact with on a daily basis are either acids or bases. Most fruits are acids, as are carbonated beverages, tea, and battery acid. Common household bases include baking soda, ammonia, soap, and antacids. What are acids and bases? ...

• ###### Acids and Bases

...BRONSTED-LOWRY ACIDS AND BASES 1. The Bronsted-Lowry definition There are many definitions of acids and bases in existence, but the most useful one is the Bronsted-Lowry definition: An acid is a substance which can behave as a proton (re presented as a hydrogen ion, H+) donor. Any substance which contains hydrogen bonded to a more elect...

• ###### Acids and Bases

...and Determination of Unknown Acid KEYWORDS: quantitative analysis, titration, buret, endpoint, standardization, half-equivalence point, calorimetric titration, potentiometric titration ABSTRACT: The concentration of sodium hydroxide was determined by colorimetric titration, and the identity of an unknown acid was determined by potentiome...

• ###### Chemistry Acid and Base

...Aqueous Acid/Base Chemistry Resources: Harris ‘Quantitative Chemical Analysis’ Review: Pure water has a pH = 7 Autodissociation: H2O (( H3O+ + OH- K = [H3O+][OH-]/[H2O] -log[H3O+] = 7 [H3O+] = 10-7 M = [OH-] [H2O] = 55.56 M K = 1.8 x 10-16 ; pKa = 15.74 pKa is the acid dissociation constant; low pKa (strong acid, h...

• ###### Acids, Bases & Buffers

...﻿Title: Acids, Bases & Buffers Objectives: 1. To understand the acid-base chemistry. 2. To prepare and evaluate a buffer system 3. To measure the buffering capacity of two types of isotonic drinks. Introduction: There are acid-forming, basic forming and neutral food, however the acid or alkaline properties of a food is unable to judge b...

• ###### Acids Bases Qs

...﻿Acids and Bases Q1.This question is about several Brønsted–Lowry acids and bases. (a)     Define the term Brønsted–Lowry acid. ........................................................................................................................ .........................................................................................

• ###### Acid Base Equilibria and Solubility Equ

...August 28, 2009 [PROBLEM SET FROM R. CHANG TEST BANK] Chapter 16 Acid-Base Equilibria and Solubility Equilibria Student: ___________________________________________________________________________ NOTE: A table of ionization constants and Ka's is required to work some of the problems in this chapter. 1. In which one of the following solutions ...

• ###### Acid-Base Buffers

...CHEMICAL REACTIONS: ACID-BASE BUFFERS Short Overview Acids and bases represent two of the most common classes of compounds. Many studies have been done on these compounds, and their reactions are very important. Perhaps the most important reaction is the one in which an acid and base are combined, resulting in the formation of wate...