“Tin hedgehog” experiment

How to grow a metal hedgehog in 5 minutes

Many of you may have heard about an­i­mals out of a test tube, but what about a metal­lic hedge­hog out of a beaker?

Safe­ty pre­cau­tions

Wear pro­tec­tive gloves, eye­wear, and a mask. Per­form this ex­per­i­ment in a well-ven­ti­lat­ed area. Ob­serve safe­ty pre­cau­tions when work­ing with con­cen­trat­ed acids.

Reagents and equip­ment:

  • piece of zinc;
  • 5g tin(II) chlo­ride;
  • 70% acetic acid;
  • dis­tilled wa­ter;
  • 2 beakers.

Step-by-step in­struc­tions

Com­bine 5 g of tin(II) chlo­ride and 95 mL dis­tilled wa­ter in the beaker. Watch as the so­lu­tion turns cloudy. Add a few drops of acetic acid – the so­lu­tion should be­come trans­par­ent.Tie the zinc pel­let to a splint or pen­cil and im­merse it in the so­lu­tion. Af­ter 4 min­utes, the zinc will be cov­ered with spiky crys­tals.

Pro­cess­es de­scrip­tion

When tin(II) chlo­ride is dis­solved, its hy­drol­y­sis takes place, and an in­sol­u­ble pre­cip­i­tate of tin(II) hy­drox­ide forms. The 70% acetic acid is added to re­verse the hy­drol­y­sis and ob­tain tin(II) ions.

[source]

Zinc is to the left of tin in the re­ac­tiv­i­ty se­ries of met­als, so it eas­i­ly forces tin out of the so­lu­tion. An ox­i­da­tion-re­duc­tion re­ac­tion takes place, and the tin is re­duced on the sur­face of the zinc in the form of beau­ti­ful spiky crys­tals.

SnCl₂ + Zn → Sn + Zn­Cl₂

Try it