Conductivity


Purpose:

  1. To determine which materials/solutions conduct electricity and why.

Materials:

  1. 5% NaCl solution
  2. Solid NaCl
  3. 5% sucrose (C12H22O11) solution
  4. Ethanol (C2H5OH)
  5. Kerosene
  6. 1M HCl
  7. 1M NaOH
  8. Glacial acetic acid (HC2H3O2)
  9. 6M acetic acid (HC2H3O2)
  10. 6M ammonia (NH3)
  11. Distilled water
  12. Tap water
  13. Conductivity apparatus
  14. 100-mL beaker

Procedure:

  1. Clean and dry beaker.
  2. Add 20 mL of 5% NaCl solution to the beaker.
  3. Plug in conductivity apparatus and immerse the electrodes into the solution at a depth of 1 cm.
  4. Make observations about the light bulb.
  5. UNPLUG the conductivity apparatus, and clean and dry electrodes.
  6. Repeat steps 1-5 with all other solutions.
  7. Record all information in the data table.

Data & Information:

Substance Bright/Dim/No Light . . . . . . . . . . . Why? . . . . . . . . . . .
5% NaCl Solution Bright/Dim/No Light Why:
Distilled Water Bright/Dim/No Light Why:
Tap Water Bright/Dim/No Light Why:
Kerosene Bright/Dim/No Light Why:
1M HCl Bright/Dim/No Light Why:
1M NaOH Bright/Dim/No Light Why:
Glacial HC2H3O2 Bright/Dim/No Light Why:
6M NH4 Bright/Dim/No Light Why:
1M NH4 Bright/Dim/No Light Why:

Questions:

  1. Compare the conductivity of solid NaCl and a 5% solution of NaCl. Explain the difference.
  2. Compare the conductivity of 6M ammonia and 1M ammonia. Explain any difference.
  3. What type of bonding is present in HCl? Explain the results of the conductivity test on HCl.
  4. Glacial acid is acetic acid that is 99.8%, containing no more than 0.2% water. Compare the conductivity of glacial acid with that of 6M acetic acid and explain the difference.