Chemistry 660 Latest News--Fall 2003

Dr. James Ingle

12/5/03

go to exam page for corrections on exam III - final

exam page

key for exam 2 is on exam page

correction on page 4-8 of lecture notes

for the S/N equation at the top,  I wrote in the positions for the circled a, b, and c in the wrong place below the denominator of the equation.  The order should have been b, c, a

go to exam page for corrections on exam II

exam page

10/29/03

supplement 8 - corrections

page one on second line of text box should read r_cp = M_pK(8)/e

go to exam page for corrections on exam I

exam page

Concept organizer 4A -

For the question about a four level laser system, the question should read

Q. For a laser based on a four-level system, does lasing require that n₂ > n₀?

Chapter 2 - Clarifications

In dealing with intensity problems with a source and a receptor

The source area or projected area is only important when calculating the radiance of the source or when calculating the radiant power hitting the receptor for the case that the source intensity is expressed in terms of radiance (not for radiant intensity or total radiant power).

The area of the receptor determines the solid angle viewed by the receptor.  The area of the source is not important for this calculation. 

The solid angle is often represented as a cone but it does not have to be a cone if the receptor is not a circle.  What is critical is the area of the receptor even if it is rectangular. The solid angle represents a cone which has a circle area equivalent to the rectangular surface area.

For conversions of intensity per nm into intensity per Hz, it is important to insure that the conversion factor of l²/c has units of nm/Hz.

Chapter 1 -Clarifications

From concept sheet 1, the calibration sensitivity is the slope of the calibration curve.  It does reveal information about precision and the ability to distinguish a difference.

Not revised below this for F03

Final F02

once test is picked up - see here for corrections or comments

due 24 hours after pickup time (plus agreed added time for tests or grading) at my office (slip under door if I am not here)

You can see me a school or e-mail with questions about the exam. I will be happy to clarify or rephrase any question. Check the course WEB site for corrections or comments.

I graded problem 7-23 incorrectly for some students.  The answer for the concentration providing a number density of a atom per cubic centimeter is 1.7 x 10^-16 M.  Turn your problem set back in for an adjustment if necessary.  

Exam II

problem 1.

questions such as in a) mean you should calculate the (analytical) signal in counts, the background signal in counts, and  the total signal in counts.

For all parts the signal and noise or standard deviation of any signal is expressed in counts. You can assume that a good blank was used to obtained the blank (background) signal and to calculate the correct analytical signal from the total signal and the blank signal.  r_F represents the analytical signal in terms of a count rate in s^-1 and the 1 x 10⁵ is the calibration slope.  

part e) there is sufficient information to calculate the detection limit and you can assume typical values for constants that do not depend on the particular experiment

problem 4.

The plus/minus number is 0.032.  The subscript just indicates that the 2 is beyond the number of significant figures that should be reported but the exact number should be used for further calculations.
 

the exam is 2 pages

due 24 hours after pickup time

no lecture on Monday

You can see me a school or e-mail with questions about the exam. I will be happy to clarify or rephrase any question. Check the course WEB site for corrections or comments.

Exam I

the entrance slit in problem 1 for parts a and b is 25 micrometers

the exam is 2 pages

due 24 hours after pickup time

no lecture on Monday

You can see me a school or e-mail with questions about the exam. I will be happy to clarify or rephrase any question. Check the course WEB site for corrections or comments.

corrections in supplements

#4 - last line on page 1, the exponential should be 10²³

#5 - near bottom of first page    W = p(D/2)²/S₁ = (p/4)/(D/S₁)² = (p /4)/(F/n)²

Q1 on page 2 - F/6 lens

http://www.chem.orst.edu/ch560-1/ch560/ch560ln.htm

Last updated on December 05, 2003