Invisible wax picture

Wax’s hydrophobic properties

What could be sim­pler than draw­ing an in­vis­i­ble pic­ture?

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.


  • glass;
  • hot wa­ter;
  • wax can­dle;
  • paint­brush;
  • wa­ter­col­or pa­per;
  • wa­ter­col­or paints.

Step-by-step in­struc­tions

Put some can­dle wax in a glass and add hot wa­ter – the wax melts and floats to the sur­face. Dip a brush in the melt­ed wax and use it to make an in­vis­i­ble paint­ing on some wa­ter­col­or pa­per. Now ap­ply some wa­ter­col­or paints to the pa­per – your hid­den im­age ap­pears!

Process de­scrip­tion

Wax is main­ly com­posed of fats and fat­ty acids, the mol­e­cules of which con­tain many groups of atoms con­sist­ing of car­bon and hy­dro­gen. Such groups don’t at­tract wa­ter mol­e­cules – in fact, they re­pel them. There­fore, wa­ter col­lects in droplets on the wax, ei­ther re­main­ing on its sur­face or bead­ing up and rolling off of it en­tire­ly. As wa­ter­col­or paints most­ly con­sist of wa­ter, they can’t per­me­ate into the wax-cov­ered sec­tions of the pa­per, and your se­cret draw­ing is re­vealed in­stant­ly!

Cool ex­per­i­ments await you in the MEL Kids sub­scrip­tion!