"A singing test tube" experiment

What can you hear when iron wool reacts with sulfur?

Can you turn an or­di­nary test tube into a mu­si­cal in­stru­ment?

Safe­ty pre­cau­tions

Wear pro­tec­tive gloves, glass­es, and a mask. Per­form ex­per­i­ment in a well-ven­ti­lat­ed area.

Reagents and equip­ment

  • glass test tube;
  • 5 g pow­dered sul­fur;
  • iron wool;
  • propane torch;
  • clamp stand.

Step-by-step in­struc­tions

Pour the sul­fur pow­der into the test tube, then in­sert the iron wool. Use the propane torch to heat the test tube un­til the sul­fur melts. Af­ter some time, the test tube will be­gin to make sound.

Process de­scrip­tion

When heat­ed, the sul­fur melts and be­gins to evap­o­rate. The hot gas col­lides with the cold walls of the test tube, cre­at­ing sound. The sul­fur gas re­acts with the iron, form­ing iron(II) sul­fide.

Fe + S = FeS