As shown in the figure, put two nails into the wooden or rubber cork and set it on a beaker. Connect the iron nail to a wire that is connected to the switch, a bulb, and a 6-volt battery. Pour some alcohol or glucose on to plate, then dip your nails in it to soak them. Despite being connected to the switch, the bulb does not light up when you turn on the switch. As soon as the beaker is empty, add the HCL solution. The light bulb now glows. This proves that whereas alcohol and glucose can not carry electricity, acid may.
