acid and bases indicators electrolysis
Materials: petri dish universal indicator solution sodium chloride, NaCl, small amount 9 volt battery electrode wires with alligator clips (preferable red and black)
1. two pencils sharpened at both ends, or two paper clips distilled water—take pictures.
2. Fill a petri dish with distilled water.
3. Add a small amount of salt and stir until dissolved. —take pictures
4. Add enough universal indicator to give a rich green color —take pictures.
5. Attach each of the wire alligator clips to one end of each pencil lead. Attach the other ends of the electrodes to the battery poles, the red wire to the positive pole, the black wire to the negative pole. Turn the projector on.
6. As electrolysis progresses, color changes will begin to occur.
7. Place a niobium magnet in the middle and discuss what happens.
1. Why is the universal indicator green when you first add it?
2. Why can we use the pencils to run a charge.
3. What is the color at the cathode?
4. What is the color at the anode?
5. What happens when you place the niobium magnet? Why?
6. What is the equation for the electrolysis of water? Without e and volts
7. Why can we dump the solution down the drain?