1
MEASUREMENT IN THE LABORATORY
INTRODUCTION
Today's experiment will introduce you to some simple but important types of measurements
commonly used by the chemist. You will measure lengths of objects,
1
MOLAR VOLUME OF A GAS
INTRODUCTION
Any substance can exist in any phase, solid, liquid or gas, depending upon the conditions
surrounding the substance. We are accustomed to certain substances existi
1
DETERMINATION OF THE MOLAR MASS OF CARBON
DIOXIDE
INTRODUCTION
Molar masses of gases can be determined in a number of ways, many of them indirect. In this
experiment you will find the molar mass dir
1
DETERMINING AND USING H
INTRODUCTION
CHANGES IN CHEMISTRY
Chemistry is the science that studies matter and the changes it undergoes. Changes are divided
into two categories: physical and chemical. D
1
ELEMENTS: THEIR PROPERTIES AND RELATIONSHIPS
Introduction
About 90 elements occur naturally on Earth. Most are found as part of compounds. For
example, all naturally occurring sodium atoms are combi
1
VIRTUAL CHEMISTRY LABORATORY  DENSITY
Introduction
In this virtual lab exercise, you will do an experiment in the Virtual Chemistry
Laboratory (VCL). During your prelaboratory meeting, your instruc
1
TITRATION OF AN ACID WITH A BASE
NOTE: You are required to view the podcast entitled Use of Burets for Titrations before
coming to lab this week. Go to http:/cms.montgomerycollege.edu/, click on Pod
1
DETERMINATION OF ACETIC ACID IN VINEGAR
INTRODUCTION
Juices from plants and fruits contain sugar. When these juices are fermented, the sugar
molecules are converted into ethyl alcohol molecules (C2H
1
VIRTUAL CHEMISTRY LABORATORY  STOICHIOMETRY
In this virtual lab exercise, you will do two experiments in the Virtual Chemistry
Laboratory. During your prelaboratory meeting, your instructor will gi
Molecular Models, Hybrid orbitals, Sigma and Pi Bonds
The shape of molecules is used in many ways to explain their behavior. Chemists use
shape to explain why a simple molecule like carbon dioxide is
1
LAB PRACTICAL
A lab practical, worth 10% of your laboratory grade, will be given at the end of the
semester during the last scheduled lab period. It will consist of primarily of short answer
and fil
Study Guide for Exam I (Chapters 0, 1, 2,3)
SustainabilityDefinition and explanation
Sustainability: Meeting the needs of present without compromising the ability of future
generations
Renewable and
Pollution
Overview
Look at any ecosystem and there could be multiple forms of contaminationstreams
full of toxic chemicals from industrial processes, rivers overloaded with nutrients from
farms, trash
Molecular Spectroscopy 42 5
We now combine Equations 13.15 and 13.16
gusJ+n=+2g+cw,QN+tEBp (BJS
gusju=a([email protected],au2 (BJQ
to nd the following equations for B] and BO:
A=gJaJ+dy%U>JD
=231+(4BQJ
=ZEQJ+D
410
Chapter 13
From Problem 1322, we know that k = 2Dy2, so
1/2
_<k y_ 1ne3Nm4
_ 20 _ 2(7.33 x 10191)
2 2.83 x 10lo ml
Recall (Equation 5.11) that the potential energy of a harmonic oscillator is U(q
412
Chapter 13
1327. The following data are obtained from the infrared spectrum of 27135Cl. Using the method of
Problem 1326, determine the values of g and 91")? from these data.
Transitions Frequency
4] 8 Chapter 13
The energies of the J levels increase as K increases for the prolate symmetric top (represented
by (a) in the diagram), but decrease as K increases for the oblate symmetric top (b). So
406 Chapter 13
The data from Table 13.3 are plotted in the following gure. (Compare the accuracy of this data to
that in the following problem.)
220
I 180
E
L)
g 140
100
2 4 6 8 10 12
J+1
The bestt l
408
Chapter 13
In the limit AG > 0, v > um. Solving for umax gives
0 = a? [1 251(va + 1)]
2ie(vmax + 1) =
1 1
v =
max 2;
The molecule dissociates in the limit AG > 0, so the dissociation energy is

Molecular Spectroscopy 405
2
R _ 4.355 x 10717 kgm2 V
9" _ (1'182;_19216294 amu) (1.661 X 1027 kgamu)
= 1.619 ><10lo m = 161.9 pm
R _ 8.604 x 1047 kgmz 2
'DI _ (2'll42_92167'9 amu) (1.661 X 1027 k
4 2 4 Chapter 1 3
The eld E causes the dipole to rotate into a direction parallel to E. Therefore, work is required to
rotate the dipole to an angle 6 to E. The force causing the molecule to rotate is
Molecular Spectroscopy
to transitions between a specic vibrational state in the upper electronic state and the various
vibrational states in the ground electronic state. The number of bound vibrationa
Molecular Spectroscopy
We use the same technique as in Problem 1331. The bestt quadratic equation to the data is
obs = ~0.O4v2 + 267.721)l + 14 005. Thus, we have
13", 2117 = 267.72 cml
( (
ECD' = 0.0
Molecular Spectroscopy 42 3
Recall that we have infrared activity only if the normal mode transforms as as x, y, or 2, which are
represented by Eu and A2. Therefore, the A I, 814, 824, and 32 vibratio
416
Chapter 13
1337. Show that the components of the moment of inertia of the trigonal planar molecule shown
below are In = Iyy = 3m/2 and lZZ = 3m if all the masses are m units, all the bond lengths
The quantity h = 4 for the C2 point group, so Equation 12.23 becomes
a
a 2
82
where we have used Table 12.7 to determine the values of X." We thus have
[151+3+3]=5
[15133]=2
[15+1+33]=4
~4>W~4>~4>I~
4  4 Chapter 13
If we subtract Ev from B we nd that
u+l
Bv+l _ Bu 2 a/
Using the values given in the problem, we then nd
v 0 1 2
cig/cm'1000592 0.00592 0.00590
Take tie = 0.00592 cm1 and substitute i