“Green lantern” experiment

How to make Green lantern from aluminum foil and copper(II) chloride

Do you dream of be­com­ing a su­per­hero? We know the eas­i­est way to do so! In this ex­per­i­ment you’ll see that you can get the Green Lantern with­out leav­ing the lab­o­ra­to­ry.

Safe­ty pre­cau­tions

Wear pro­tec­tive gloves, a mask and glass­es, and work in a well-ven­ti­lat­ed room.

Reagents and equip­ment:

  • sat­u­rat­ed so­lu­tion of cop­per(II) chlo­ride;
  • alu­minum foil;
  • con­ic flask;
  • lighter.

Step-by-step in­struc­tions

Pour the so­lu­tion of cop­per(II) chlo­ride into the flask, then add balls of alu­minum foil. The foil be­gins to dis­solve vi­o­lent­ly, with the re­lease of gas and a dark red sed­i­ment. Light it. Watch a green flame ap­pear.

Pro­cess­es de­scrip­tion

Alu­minum is a rather in­ert met­al in or­di­nary con­di­tions, as it is cov­ered with a durable pro­tec­tive ox­ide film. But in a so­lu­tion of cop­per(II) chlo­ride it dis­solves vi­o­lent­ly, with the re­lease of metal­lic cop­per and col­or­less hy­dro­gen gas. This hap­pens be­cause the so­lu­tion con­tains chlo­ride ions which eas­i­ly de­stroy the ox­ide film. As a re­sult, the alu­minum re­acts with wa­ter mol­e­cules:

2Al + 6H₂O → 2Al(OH)₃ + 3H₂

It also forces cop­per ions out of cop­per(II) chlo­ride:

2Al + 3Cu²⁺ → 3Cu + 2Al³⁺

If we light the hy­dro­gen re­leased, it will burn with a green flame be­cause of the pres­ence of cop­per ions.