Questions tagged [radioactivity]

Questions relating to radioactive substances and the chemistry of radioactivity. Also, use [rare-earth-elements] if the question is about their radioactivity specifically.

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Is lead radioactive?

Is lead (Pb) radioactive? I have heard about it being radioactive but have also heard it referred to as the heaviest stable element. Radioactivity refers to release of alpha, beta, gamma rays.
user15758
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Why do all radioactive decay series terminate at lead?

Thorium series: Uranium series: Actinium series: Why do all the radioactive decay series terminate at lead isotope? Why not hydrogen? (All pictures were taken from Wikipedia.)
Nilay Ghosh
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What is the benefit of using Am-241 in smoke detectors even though it is a radioactive element?

I see the labels denoting Am-241 in my smoke detectors. I am having a hard time understand why Am-241 is used in smoke detectors even though it is a radioactive element. It seems to me like a lot of trouble to use a radioisotope in consumer products…
Jogoo Jeje
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Half-Life of Radioactive Isotopes: Why? How?

Why do radioactive isotopes have a half-life? I know that they decay in order to become stable but why would it take out enough subatomic particles to be half? Or am I approaching this question the wrong way: the remaining radioactive substance is…
Bluedragon01313
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Nuclear Testing and Carbon Dating

Will the nuclear testing done during the past decades or if a nuclear war happened in the present day, affect the accuracy of carbon dating in the future? (Hypothetically, we haven't developed a better dating method) I mean you could just adjust the…
Chronos
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Why is astatine so radioactive?

I have heard and read about astatine's radioactivity, and it makes no sense to me. Why is it so unstable? Uranium has a half life ranging from 70 to 4.5 billion years (natural isotopes), and it has 7 extra protons to deal with. I know that atomic…
user31582
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Radioactive Decay Process

Please bear with my long winded description. It is classical to model radioactive decay of some particles $A \rightarrow A^\ast$ by the differential equation \begin{align} \frac{\mathrm dN_A}{\mathrm dt}=-\lambda N_A \end{align} where $N_A$…
Jacky Chong
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Nuclear reactions involve naked nuclei only. True or false?

In nuclear reactions are all the species involved, naked nuclei that is, are they all atoms that have been completely stripped of their electrons? If not, then shouldn't an alpha decay result in the formation of an anion and shouldn't a beta decay…
Swaroop Chandra
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Has the half-life of an isotope ever been accurately predicted before it could be measured?

The half lives of many radioactive isotopes have been measured directly. But are their half-lives known to be a function of their composition? In other words, can someone say "given an atom with this many protons, neutrons and electrons, and given…
Nathan Long
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Why is tellurium-128 so stable compared to the other radioisotopes?

Tellurium-128 is the longest lived radioisotope so far with a half-life of 2.3 septillion ($2.3*10^{24}$) years. I know I've heard something about so called "magic numbers" that if you have the perfect amount of protons and neutrons in an atomic…
Bruh Moments
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In a sample of radioactive substance all the atoms don't disintegrate simultaneously. Why?

Radioactivity though spontaneous all the atoms don't disintegrate at a time
CS DWIBEDY
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Does the decay of Carbon-14 effect health in biological systems?

Please note that this is not fundamentally a Biology question. It relates to the properties of molecules containing Carbon and Nitrogen. Carbon atoms are everywhere in living systems from sugars to proteins etc. Carbon-14 is present in living…
Kantura
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Why is an atom with excess neutrons unstable?

In this chart, I can see that stable nuclides (other than hydrogen) have a neutron count greater than or equal to their proton count, and that the neutron:proton ratio for stable nuclides increases with atomic number. I can also see that in many…
Nathan Long
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Does Suncream have any affect or help protect against radiation

So I was just watching the HBO series Chenoybl and saw that people suffered various degreesvof burns from radiation form Uranium 235 and some were very minor and looked like a normal sun burn. My question is, does Suncream protect against radiation…
Sim_ba
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Radioactivity of Promethium

In school I was taught while looking at the difference between lanthanides and actinides that all of the actinides were radioactive, while only promethium among the lanthanides was radioactive. The question that struck my mind was 'why only…
Harikrishnan M
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