Colorful Electrolysis

Procedure-

1.Broke pencil lead in half + attached them to opposite sides of the petri dish with the alligator clips.

2. Snap in the alligator clips to the 9 volt battery.

3. Measure 25 mL of sodium sulfate with the graduated cylinder.

Introduction - This demonstration was a decomposition reaction. It was telling us how chemicals break apart with electricity.

4. Pour the sodium sulfate into the petri dish and watch the decomposition reaction occur.

Scientific Principles-

When the electric current passes through the aqueous solution containing sodium sulfate (an electrolyte), the water molecules break apart into hydrogen and oxygen.

• On one side of the petri dish: 4H2O=> 2H2 + 4OH

• On the other side of the petri dish: 2H2O => O2 + 4H

Safety Regulations- Wear goggles and an apron at all times.

Materials - Petri Dish, pencil lead, alligator clips, 9 volt battery, a 25 mL graduation cylinder, and 25 mL sodium sulfate.