Select the following part of the microscope that is grabbed in order to change objective lenses from one magnification to another.

The oil-immersion objective lens, after being used, should always be wiped off with 

Which are you most likely to use when initially focusing on a sample under the 4x objective (scanning) lens.

Congratulations! Upon completion of your CHEM 3101 course, you have been hired by the City of Los Angeles’ Bureau of Criminal Apprehension analytical lab. Your group has been called in to investigate an ongoing crime that occurred at a company holiday party.

To save time, the criminal decided to determine how many untraceable bearer bonds were in the vault by weight instead of counting. Upon investigation by your team, the scale was incorrectly calibrated and records 1.000g as 0.996g each time. What type of analytical error is this?

You have learned more in this semester than I can test on a single exam. If you studied something that I did not ask on the exam and would like to explain the concept or technique to me here you may do so. Correct explanations will receive 3 bonus points.

Calculate the pH of a 0.020M KOH solution with an ionic strength of 0.10M. At m=0.10M gH+=0.83, gOH-=0.76.

Which statement(s) is(are) INCORRECT when the copper and a SCE reference electrode are connected?

At some point during the crime the fire alarm was triggered and some water splashed on a small stack of bearer bonds. This has caused some of the dye on the bonds to run, which does not happen on authentic bonds. Your boss wants you to determine what type of ink it is using UV-Vis absorption spectroscopy. You think it might be Prussian blue dye. A 5.50×10-6 M sample of the dye has an absorbance of 0.554 in a 1.00cm cuvette. A) (4 pts) What is the molar absorbance coefficient for the dye? B) (4 pts) Sketch a box diagram of a typical UV-vis spectrometer and label the components C) (2 pts) It turns out that the sample of dye you are able to retrieve from the bonds is too dilute, how could you change your UV-vis setup to increase the absorbance for your sample?

I understand that I am not allowed to use any outside devices including smart phone, tablets, laptops, etc.