Because all the particles formed are radioactive.
The decay of a uranium-238 atom into lead-206 involves the emission of 8 alpha particles. This decay process releases 8 helium-4 (α) particles as the uranium nucleus undergoes multiple decay steps to stabilize as lead-206.
3 steel steps
There is about 10 steps leading up to the Parthenon
Element number 92 is Uranium and there are two main isotopes - U235 and U238. In U235 there are 92 protons so there are 235 - 92 = 143 neutrons. In U238 there are thus 146 neutrons
about 30-36 steps
There is about 50 steps leading up to the parthenon.
U-238 is the most abundant (99.3%) of the three naturally occurring isotopes of Uranium. The other two are U-235 and U-234.U-238 decays spontaneously to Thorium-234 by alpha particle emission. This decays by beta decay to Protactinium-234 and then that undergoes beta decay to become U-234.There are many more decay steps by alpha and beta emission. The end result is Lead-206 which is stable.The full path can be found in the Argonne National Laboratories Human Health Fact Sheet, August 2005, titled Natural Decay Series: Uranium, Radium, and ThoriumThis is found at:http://www.ead.anl.gov/pub/doc/natural-decay-series.pdf
tell me tell me
tell me tell me
656source: http://www.algherosardinia.net/neptunes-grotto.html
Yes, many things decay and decompose.
No. Many atoms do not decay at all. Many that do undergo alpha decay. A few atoms emit neutron radiation.