Last modified: Wed 12/31/1969 06:00:00 pm
BCE

Oklahoma State University

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Answer all of the questions below. If you do not know an answer enter CNA. However, it will help me the most if you answer each question with your best intuition/idea about what would be a reasonable answer.


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In this BCE I would like you to investigate the conductivity behavior of a set of substances to identify any pattern(s) that you observe and then to write a summary statement that generalizes your observations. In the table below are three lists of compounds: Salts, Acids and Bases.

Substances (Salt)

Substances (Acid)

Substances (Base)

NaCl

HCl

NH3

NH4NO3

H2SO4

HONH2

NH4Cl

HC2H3O2

NaOH

NaC2H3O2

HF

Ca(OH)2

Na2SO4

HC3H5O3

(CH3)2NH

NaCN

HNO3

C6H5NH2

NaNO3

HClO2

Ca(OH)2

NaF

HNO2

 

(NH4)2SO4

 

 

Here is an mp4 movie that contains several of the salts, an mp4 movie that contains all of the acids and an mp4 movie that contains all of the bases. After the movie opens you can use the control bar to find your particular compound. For each list (salts, acids and bases) write a brief summary statement that represents the nature of the compounds in the list and your observations of their conductivity. This summary statement would most likely read like a rule. Prior to each summary statement is a table where you can enter the formula of each compound you test and the conductivity of that compound.

For each test you are to use approximately the same volume (within a milliliter or two). You are to observe the brightness of the bulb. The bulb brightness is a measure of the number of ions in solution. Use a scale from 1 (no intensity) to 5 (very bright) to indicate the level of brightness for your measurement.

(The movie will open in another window, to return to the BCE either close the Flash movie window or re-adjust its size and move it aside to get to the BCE window behind and answer the questions.)

1a. Complete the table below for some of the salts conductivity shown in the movie.

Salts:

Substance (formula)

Conductivity (bulb brightness)

b. Enter your summary statement about the conductivity of the salts that you tested.

2a. Complete the table below; mp4 movie that contains all of the acids

Acids:

Substance (formula)

Conductivity (bulb brightness)

b. Enter your summary statement about the conductivity of the acids that you tested.

3a. Complete the table below; mp4 movie that contains all of the bases

Bases:

Substance (formula)

Conductivity (bulb brightness)

b. Enter your summary statement about the conductivity of the bases that you tested.

 

4a. The last option in the simulation is Unknown(s). Test the conductivity of each of the unknowns and then identify what you believe the unknown to be. Here is an mp4 movie that contains Unknown solutions.

Complete the table below;

Bases:

Unknown #

Conductivity (bulb brightness)

1

2

3

4

5

6

b. What do you think Unknown#5 is?

4. Is there anything about the questions that you feel you do not understand? List your concerns/questions.

5. If there is one question you would like to have answered in lecture, what would that question be?