Search results
Results From The WOW.Com Content Network
In nuclear science a decay chain refers to the predictable series of radioactive disintegrations undergone by the ... 232 Th does this when it decays into radium-228.
Radium (88 Ra) has no stable or nearly stable isotopes, and thus a standard atomic weight cannot be given. The longest lived, and most common, isotope of radium is 226 Ra with a half-life of 1600 years. 226 Ra occurs in the decay chain of 238 U (often referred to as the radium series). Radium has 34 known isotopes from 201 Ra to 234 Ra.
226 Ra is the most stable isotope of radium and is the last isotope in the (4 n + 2) decay chain of uranium-238 with a half-life of over a millennium; it makes up almost all of natural radium. Its immediate decay product is the dense radioactive noble gas radon (specifically the isotope 222 Rn ), which is responsible for much of the danger of ...
The 4n decay chain of 232 Th, commonly called the "thorium series" Thorium-232 has a half-life of 14 billion years and mainly decays by alpha decay to radium-228 with a decay energy of 4.0816 MeV. [3] The decay chain follows the thorium series, which terminates at stable lead-208. The intermediates in the thorium-232 decay chain are all ...
Its decay chain is the thorium series, eventually ending in lead-208. The remainder of the chain is quick; the longest half-lives in it are 5.75 years for radium-228 and 1.91 years for thorium-228, with all other half-lives totaling less than 15 days. [55]
The alpha decay of 232 Th initiates the 4n decay chain which includes isotopes with a mass number divisible by 4 (hence the name; it is also called the thorium series after its progenitor). This chain of consecutive alpha and beta decays begins with the decay of 232 Th to 228 Ra and terminates at 208 Pb. [17]
The longest lived isotope of radium is radium-226 with a half-life of 1600 years; it along with radium-223, -224, and -228 occur naturally in the decay chains of primordial thorium and uranium. Beryllium-8 is notable by its absence as it splits in half virtually instantaneously into two alpha particles whenever it is formed.
228 Th (α, 1.9 year) 224 Ra (α, 3.6 day, 0.24 MeV) (from this point onwards, the decay chain is identical to that of 232 Th; thorium-232 is nevertheless much less dangerous because its extremely long half-life of about 14-15 billion years means that not as much of its dangerous daughters builds up) 220 Rn (α, 55 s, 0.54 MeV) 216 Po (α, 0.15 s)