The world's first battery

Safe­ty pre­cau­tions

Warn­ing! Only un­der adult su­per­vi­sion.

Equip­ment

• cop­per to­kens;
• mag­ne­sium and steel plates;
• cloth soaked in sodi­um chlo­ride so­lu­tion;
• croc­o­dile clips;
• LEDs;
• small pro­pel­ler;
• buzzer.

Step-by-step in­struc­tions

Set two mag­ne­sium to­kens on a steel plate, then place a piece of cloth soaked in sodi­um chlo­ride so­lu­tion and a cop­per to­ken on each one. Re­peat the pre­vi­ous step twice more for each stack (to­talling three mag­ne­sium to­kens, three pieces of cloth, and three cop­per to­kens in each stack), then top the con­struc­tion off with one last steel plate. Con­nect croc­o­dile clips to the steel plates – an elec­tric po­ten­tial of about 4 V ap­pears be­tween them! You can use them to fire up a small pro­pel­ler, light an LED, and even make a buzzer buzz!

Process de­scrip­tion

When you close the cir­cuit with the croc­o­dile clips con­nect­ed to, for ex­am­ple, an LED, the cop­per and mag­ne­sium be­gin to re­act with the salt so­lu­tion. Elec­tric po­ten­tial aris­es, and elec­tric cur­rent ap­pears, caus­ing the LED to light up! Even just a few met­al plates will suf­fice – mag­ne­sium is an ex­treme­ly re­ac­tive met­al!

Cool ex­per­i­ments await you in the MEL Chem­istry sub­scrip­tion!