pshh, how should i know? Haha, just kidding! but i really dont know..
Americium 241
Americium (isotope 241) is the most common radioactive element used in smoke detectors.
A radioactive element is an element that emits radiation due to instability. They are commercially used in the generation of electricity in nuclear power plants and home smoke detectors among other things.
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Radioactive elements are not used in the treatment of AIDS.
Americium-241 this is an emitter of alpha radiation, which is used in smoke detectors as it is very ionising and will not be able to travel through smoke. Therefore, in a fire the detector will not receive any alpha radiation and hence the alarm will go off.
Nitrogen-Building block of proteins
Uranium
iodine
LEAD
lead
cobalt