“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!

Safe­ty pre­cau­tions

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);
  • cup;
  • cot­ton swab;
  • pa­per;
  • elec­tric­i­ty source;
  • diode.

Step-by-step in­struc­tions

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.

Pro­cess­es de­scrip­tion

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.