Fake Blood With Knife Chemistry Trick

Fake Blood With Knife Chemistry Trick Heres a cool chemistry trick, perfect for Halloween! Trace a knife over your skin and leave a message that appears to be written in blood. The project works equally well with a spoon  but somehow loses impact. Try it... Bleeding Knife Materials You only need a few materials for this project, however, youll either need access to a lab for the chemicals or else you can order them online. Dull knife (we dont need real blood here)5 grams ferric chloride5 grams potassium thiocyanateWater Prepare the Magic Solutions Prepare saturated solutions. Youll know the solutions are saturated if no additional solid will dissolve in the liquid. Mix a few milliliters of water with the ferric chloride to dissolve it.Separately, mix a few milliliters of water with the potassium thiocyanate to dissolve it. Perform the Trick Coat the area of skin to be bloodied or written on with the potassium thiocyanate solution. Youll get the best effect (dripping blood) if the skin remains damp, but the color appears just fine even if you let the area dry.Dip the knife blade in the ferric chloride solution.Draw on your skin with the dampened knife blade. A deep red liquid resembling blood will appear where the two solutions mix. How It Works This chemistry trick is one form of a sensitive test for the ferric ion. A red color is produced by the reaction between the ferric ion and the thiocyanate ion. Bleeding Knife Clean-Up and Safety When youre done, rinse the blade and your skin under running water to remove the chemicals. The demonstration is safe to perform, but restrict the project to your arm or hand and avoid eyes, nose or mouth to avoid ingestion of the chemicals or irritation of mucous membranes. More Halloween Chemistry Apply chemistry for more Halloween fun. You can make a glow-in-the-dark jack-o-lantern, slime that looks like ghostly ectoplasm, or a mad scientist Halloween costume.