Manganese traffic light

How to make a traffic light from potassium permanganate

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.

Reagents and equip­ment

  • potas­si­um per­man­ganate so­lu­tion;
  • al­ka­line glu­cose so­lu­tion (glu­cose so­lu­tion + drain clean­er);
  • glass.

Step-by-step in­struc­tions

Mix a potas­si­um per­man­ganate so­lu­tion with an al­ka­line glu­cose so­lu­tion (glu­cose so­lu­tion + drain clean­er). Ob­serve as the so­lu­tion changes col­ors like a traf­fic light.

Process de­scrip­tion

In an al­ka­line medi­um, glu­cose re­duces potas­si­um per­man­ganate, first to potas­si­um man­ganate, and then to man­ganese(IV) ox­ide. In this case, the so­lu­tion changes col­ors from rasp­ber­ry-red to green, then to brown.

Cool ex­per­i­ments are wait­ing for you in the MEL Chem­istry sub­scrip­tion!