Concept Test 1

Internet Concept Test Chemistry 22

Prof. J. C. Baird

Forms, CGI and Database by Marn-Yee Lee

Topic: The Kinetics of Oxidation of Glucose

A Question of Competitive Rate Processes

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Question 1

A solution is prepared, consisting of glucose, hydroxide ion and a dye and placed in a flask which is immediately stoppered, trapping an air space. The following observations are made. (Note: we are trying to figure out what is going on in this reaction from the given information. There are four questions.)

  1. When the dye is first added the solution turns blue taking a few seconds.
    2. Flask with blue solution (Blue)
  2. Immediately after the flask is stoppered, the solution gradually bleaches taking tens of seconds.
  3. The blue disappears uniformly throughout the solution.
    4. Flask with white solution (White)

The meaning of these facts are:

Reason for Answer:

Question 2

The stoppered flask is shaken once and the blue color returns quickly then bleaches taking about 10 sec.

The meaning of these facts are:

Reason for Answer:

Question 3

  • An experiment is done correlating the number of shakes with the time taken to bleach.

    • Number of Flask Shakes Bleach Time in Seconds
    1 10
    2 15
    3 20
    4 25
    5 30

    The meaning of these facts are:

    Reason for Answer:

    Question 4

    How do we account for both an increase in time the solution stays blue in color and simultaneously a constant color intensity regardless of the concentration of dissolved gas?[1]
    1. J. A. Campbell, Kinetics-Early and Often, J. Chem. Ed. 40, 578 (1963)
    Reason for Answer:

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