Several students were studying five compounds. They wanted to see if the compounds would conduct electricity when dissolved in water. A small sample of each compound was placed in a beaker, and 100 mL of pure water was added. Each sample dissolved in the water. A conductivity tester was placed in each beaker. A glowing green bulb meant the sample was a conductor. A glowing red bulb meant the sample was not a conductor.

Question

A Conductivity Tester Red bulb
Green bulb
The students recorded the results in a data table.
Conductivity Test of Five Compounds
Compound
NaI
СНО
Zn(NO3)2
Observation
Green bulb glowed.
Red bulb glowed.
Green bulb glowed.
Li2SO
Green bulb glowed.
CH,OH
Red bulb glowed.

Answer 1

Based on the results from the conductivity test of the five compounds, we can summarize the observations as follows:

1. NaI - Green bulb glowed (Indicating it is a conductor of electricity)
2. C₂H₅OH (Ethanol) - Red bulb glowed (Indicating it is not a conductor of electricity)
3. Zn(NO₃)₂ - Green bulb glowed (Indicating it is a conductor of electricity)
4. Li₂SO₄ - Green bulb glowed (Indicating it is a conductor of electricity)
5. CH₃OH (Methanol) - Red bulb glowed (Indicating it is not a conductor of electricity)

From these observations, we can infer the following:

• Conductive compounds generally contain ions that dissociate in solution and allow the flow of electricity.
• NaI, Zn(NO₃)₂, and Li₂SO₄ are ionic compounds that dissociate into ions when dissolved in water, which is why they conduct electricity (green bulb).
• C₂H₅OH (ethanol) and CH₃OH (methanol) are molecular compounds and do not dissociate into ions in solution, which is why they do not conduct electricity (red bulb).

Summary

• Conductors: NaI, Zn(NO₃)₂, Li₂SO₄
• Non-conductors: C₂H₅OH, CH₃OH