“Liquid wires” experiment
How to make wires from graphite and water glass
In this experiment, you’ll find out how to use a single “paint” to draw a picture that conducts electricity!
Wear protective gloves and glasses.
A similar experiment is included in the MEL Chemistry subscription
Reagents and equipment
- 5g graphite powder;
- 10g “liquid glass” (sodium silicate solution);
- cotton swab;
- electricity source;
Mix 10mL liquid glass and 5g graphite powder in a cup. Use a cotton swab to transfer the mixture to a piece of paper. You can draw anything you want, but it must start at the edge of the paper, and the line must be continuous, as shown in the video. Connect the two wires to the electricity source. Then attach the clip of the first wire to the edge of the paper, where the drawing begins. Attach the clip of the second wire to the diode. Touch the long prong of the diode to the line, and watch the diode glow.
Graphite is a good electrical conductor, and the liquid glass glues its particles together to make a continuous circuit. Electrons start moving from one particle of graphite to another. When we close the circuit with a diode, current flows through it and the diode lights up. These “wires” can be applied to any surface in the form of any drawing. But the line must be unbroken, otherwise the circuit will not close and a current will not flow through it.