What differs between a radioactive isotope and a stable isotope?

Radioactive isotopes last longer.

Radioactive isotopes last for less time.

Stable isotopes are shorter.

There is no difference. @AloneS

Question

What differs between a radioactive isotope and a stable isotope?
		
Radioactive isotopes last longer.
		
Radioactive isotopes last for less time.
		
Stable isotopes are shorter.
		
There is no difference. @AloneS

helpmethx · Answer

I was thinking it was the second one because, I know radioactive isotopes are unstable

alones · Answer

Hrmm

alones · Answer

This seems difficult, but i'd go with B, since C &A have something in common.

osprey · Answer

Radioactive isotopes DECAY because they're radioactive. Therefore they last a shorter time than stable isotopes. Carbon dating uses this. The isotope of carbon, carbon 14 is radioactive. It takes a very, very long time to decay, and this is used in dating of things to see how old they are. A thing called the HALF LIFE is used to measure the radioactive decay. It can vary from years to seconds to tenths of a second etc. Bon voyage http://perendis.webs.com