Decay rate = kN
1. Convert ng to g:
1.0ng = 1.0 x 10^-9g
2. Convert g to atoms
N = (1.0x10^9 g)(1mol 44Ti/44g)(6.022x10^23atoms/1mol) = 1.37x10^13 atoms
3. Use the eqn at the top to find k
k = decay rate/N = (4.8x10^3dps)/(1.37x10^13 atoms) = 3.51x10^-10 s^-1
4. Use Half-Life eqn to find t1/2
t1/2 = 0.693/k
t1/2 = 0.693/(3.51x10^-10 s^-1) = 1.98x10^9 s
5. Convert seconds to years
1.98x10^9 s/60 = 3.30x10^7 min/60 = 5.50x10^5 hours/24 = 2.29x10^4 days/365 = 62.78 years ~ 63 years
A sample of 187 rhenium decays to 187-omium with halflife of 41.6 billion years. If all 188 osmium are normalized isotopes.
Uranium 238 is aan alpha particles emitter: halflife 4,468.109 years, energy 4,270 MeV.
It,s half life.The time it takes to emit 50% of the radioactive emission it did when first counted.
- intermediate in the preparation of plutonium 238 - in the instruments for the detection of high energy neutrons - possible use in the future as material for nuclear weapons - possible use in the future as nuclear fuel
decays
Curie: A unit of radioactivity equal to 3.7 � 10^10 Disintegrations (decays) per second.
A sample of 187 rhenium decays to 187-omium with halflife of 41.6 billion years. If all 188 osmium are normalized isotopes.
Uranium 238 is aan alpha particles emitter: halflife 4,468.109 years, energy 4,270 MeV.
It,s half life.The time it takes to emit 50% of the radioactive emission it did when first counted.
238U radiates alpha particles and decays via 234Th and 234Pa into 234U, which has a halflife of 245,500 years. (Thorium-234, Protactinium-234, Uranium-234 respectively)
The basic idea is to compare the abundance of a naturally occurring radioactive isotope within a material to the abundance of its decay products; it is known how fast the radioactive isotope decays.
- intermediate in the preparation of plutonium 238 - in the instruments for the detection of high energy neutrons - possible use in the future as material for nuclear weapons - possible use in the future as nuclear fuel
Eventually residual radioactivity decays, people rebuild. People always rebuild, regardless of the disaster.Actually reactor disasters, like Chernobyl, are much worse than any nuclear bomb. The worst bomb incident (shallow subsurface multi-megaton yield) generates only a few tons of mostly short halflife fallout, the area may be safe in as little as a few weeks; a reactor contains thousands of tons of mostly long halflife isotopes which if released in a steam explosion and fire, like Chernobyl, will contaminate an area for many many generations.Note: I am ignoring salted/dirty nuclear bombs deliberately designed to produce lots of long halflife fallout.
Carbon-14 decays by beta-, which emits a W- boson that immediately decays into an electron and an electron anti-neutrino.
When a mineral spontaneously decays into subatomic particles, it has this property
For decays by alpha emission use the general formula: A/Z X --> 4/2 He + A-4/Z-2 Y *Where A is atomic mass and Z is atomic number. So for U-238 238/92 U --> 4/2 He + 234/90 Th
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