Last modified: Fri 09/23/2016 11:02:07 am 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.


First Name:

Last Name:

School:

In this BCE I would like you to investigate the conductivity behavior of a set of substances 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

 

 

Open the Flash animation using the link below and test the conductivity of a subset of the substances from each of the three lists. 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.

Here is the link to the Flash animation

(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;

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;

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;

Bases:

Substance (formula)

Conductivity (bulb brightness)

b. Enter your summary statement about the conductivity of the acids 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.

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?