How to make a plaster ghost

Easy Halloween ghost craft

Are we in Area 51? No, these are just some awe­some plas­ter ghosts!

Safe­ty pre­cau­tions

Only un­der adult su­per­vi­sion.

Equip­ment and reagents

  • 120g plas­ter of Paris;
  • 200mL wa­ter;
  • bal­loon;
  • gauze;
  • dish;
  • plas­tic wrap;
  • eye;
  • and mouth stick­ers.

Step-by-step in­struc­tions

Mix 120g plas­ter of Paris and 200mL wa­ter in a bowl. Cov­er a deep dish with plas­tic wrap and pour the plas­ter so­lu­tion into it. Dip some gauze in the so­lu­tion and ar­range it on a bal­loon. Let sit 24 hours. Just add eyes and a mouth, and your plas­ter ghost is ready!

Pro­cess­ de­scrip­tion

Plas­ter of Paris, or gyp­sum plas­ter, is semi-aque­ous cal­ci­um sul­fate Ca­SO₄·0,5H₂O. It is ob­tained by heat­ing gyp­sum – cal­ci­um di­hy­drate sul­fate Ca­SO₄·2H₂O – to 150-180°C. The lat­ter oc­curs nat­u­ral­ly in min­er­al form, most­ly as se­len­ite. When mixed with wa­ter, gyp­sum plas­ter pow­der hard­ens rapid­ly, re­vert­ing to cal­ci­um sul­fate di­hy­drate. This prop­er­ty of gyp­sum makes it use­ful in con­struc­tion, sculp­ture, and medicine (i.e. plas­ter casts). When it is hy­drat­ed, it can be used to mold things, such as the form of an awe­some ghost! Want more? You can do many oth­er cool ex­per­i­ments us­ing the sets from the MEL Chem­istry sub­scrip­tion!