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Why does decay chain for radioisotope U-238 eventually stop at lead?
Wiki User
∙ 13y ago
The isotope of lead formed is stable. No other isotope in that decay chain is.
Wiki User
∙ 13y ago
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Is half life the same for each isotope?
The term half life describes the rate at which the isotopes of a particular atom decay. Thus, if you have a lump of Uranium 238 (U238), then the atoms in the lump will decay at the same rate as the half life. If that lump was created four billion years ago and it consisted of 100% U 238, today the lump would be half U238 and half something else, mostly lead. That would go for both the atoms and the whole lump. If the lump consisted of 10% U238 today it would consist of 5% U238, and 95% something else. The fact that the U238 has a half life of 4 billion years only affects the Uranium and nothing else.
How can the radioactive nuclide plutonium 239 be prepared using nuclear equations?
U238 + n --> U239 : capture, crosssection 2.73 barnsU239 --> Np239 + e- : beta decay, half-life 23.5 min.Np239 --> Pu239 + e- : beta decay, half-life 2.33 days
What do you called in an element having the same atomic number but different atomic masses?
Isotopes. eg U235 and U238. Both Uranium, atomic number 92, bur different isotopes.
What is a balanced nuclear equation for the alpha decay of Rn-22?
I'm assuming we are talking about Rn222. Rn222 is part of the U238 chain (also known as the Radium series). Rn222 (half life 3.8 days) -> Po218 + alpha particle (5.59 MeV) Po218 (half life 3.1 minutes) -> Pb214 + alpha particle (6.115 MeV) Pb214 (half life 26.8 minutes) -> Bi214 + beta- particle (1.024 MeV) Bi214 (half life 19.9 minutes) -> Po214 + beta- particle (3.272 MeV) Po214 (half life .164 ms) -> Pb210 + alpha particle (7.883 MeV) Pb210 (half life 22.3 years) -> Bi210 + beta- particle (64 keV) Bi210 (half life 5.013 days) -> Po210 + beta- particle (1.426 MeV) Po210 (half life 138.4 days) -> Pb206 + alpha particle (5.407 MeV) Pb206 (lead) is stable so that is the end of the chain.
What is U235?
2 different isotopes of uranium. isotope= element with same number of electrons, same number of protons, different numbers of neutrons. U235 has 143 neutrons and 92 protons U238 has 146 neurtons and 92 protons
What does the breakdown of uranium release?
U238 releases a small part called alpha radiation and a large part known as the decay product.
Is half life the same for each isotope?
The term half life describes the rate at which the isotopes of a particular atom decay. Thus, if you have a lump of Uranium 238 (U238), then the atoms in the lump will decay at the same rate as the half life. If that lump was created four billion years ago and it consisted of 100% U 238, today the lump would be half U238 and half something else, mostly lead. That would go for both the atoms and the whole lump. If the lump consisted of 10% U238 today it would consist of 5% U238, and 95% something else. The fact that the U238 has a half life of 4 billion years only affects the Uranium and nothing else.
What is one of the daughter elements of urainium-238?
U238 is a stable isotope of uranium - it doesn't undergo decay except at a very very slow rate unless hit with Neutrons - then it will decay to Neptunium
Is Pb-206 radioactive?
Yep! It is the last product in the chain of decay of Radium and Uranium series. There are a lot of nasty products that they decay into before becoming lead-206 (which takes about 4.5 billion years) but once there, the final product: "lead-206" should not give you cancer as it is stable (non-radioactive). Don't eat it of course because it's still poisonous (chemically).
What is meant by reactor grade materials?
This means that the nuclear material is of a high enough concentration to fissile (allow for a fission chain reaction). This is because Uranium comes naturally as 99.3% U238, which cannot sustain fission, and .7% U235, which is what they want for the fuel. So they have to find away to pull away the U238 and leave the U235. As they concentrate the U235, it becomes concentrated enough so that it can sustain fission (too much U238 bogs down the reaction and will eventually end the fission). When it reaches this point of concentration, it is concidered reactor grade. Different elements have different needed concentrations to reach this level.
How can the radioactive nuclide plutonium 239 be prepared using nuclear equations?
U238 + n --> U239 : capture, crosssection 2.73 barnsU239 --> Np239 + e- : beta decay, half-life 23.5 min.Np239 --> Pu239 + e- : beta decay, half-life 2.33 days
What keeps the rocks inside the earth in molten state?
Radioactive decay in the inner core of k40 U238 and Th232 cause the earths internal heat plus lithostatic pressure (pressure of the overlying rocks).
What is the atomic number of radon -222?
Radon has atomic number 86. That means it has 86 protons. The specific isotope doesn't matter. (It does matter if you want to figure out the number of neutrons, though.)
How many neutrons are in Element 92?
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
Is uranium nuclear fuel?
Yes, U233, U235, and U238 are all used as nuclear fuels.
Is Radon abundant?
A2. Radon is a decay product of Uranium, and is about 6 radioactive decay steps from U238. The Uranium occurs in some granite rocks, and as buildings are often made from this durable rock, Radon is generated from the building fabric. It is considered that exposure to Radon gas is second only to cigarettes as the cause of lung cancers in the US. Some unfortunate towns, such as Dundee, sit on the granite and build the houses of it, and this is a serious local problem. Basements and attics should have adequate ventilation to remove the gas.It is not an abundant gas, and perhaps there are some tens of grams of Rn in the Earth's atmosphere. This eventually decays into lead, and is continuously replaced by new Rn from U decay.
Is Thorium-234 Proactinium-234 -1 a alpha decay equation?
It's beta decay. Actually, it's beta minus decay. A neutron in the nucleus of thorium-234 undergoes beta minus decay and changes into a proton with the subsequent release of an electron, an antineutrino and some energy. The transformation of a neutron in the thorium nucleus into that proton creates another element. You'll recall that the identity of an element is determined solely by the number of protons in its nucleus. And our thorium atom has now become a protractinium-234 atom. Links are provided below for more information.
