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What are the first 5 elements by atomic number for which all isotopes are radioactive?
Wiki User
∙ 6y ago
43 Technetium, and 61 Promethium have no stable isotopes. All elements starting at 83 Bismuth have only radioactive isotopes; though Bismuth-209 has such a long half-life that it can be considered stable for any practical purpose.
Wiki User
∙ 6y ago
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Radioactive elements comprise a majority?
Yes. Stable elements are 83 elements. all elements above that of atomic number 83 (Bismuth) are radioactive. Radioactive isotopes are of the order of 1500 radioactive isotope.
All isotopes of this element are radioactive?
Radioactive Elements (38) These elements are radioactive. They either have no stable naturally occurring isotope, or else are entirely artificial (all artificial elements have no stable isotopes). by Andrew Moore
What is the first radioactive element number?
Of elements that have no stable isotopes, technetium has the lowest atomic number, which is 43.
How many stable nuclides exist for elements that have and atomic number above 83?
All isotopes of all elements with atomic number similar or greater than 84 are radioactive, and don't have stable nuclei.
Which element has an atomic mass of11?
Atomic mass numbers are not properties of elements overall, but only of particular isotopes of elements. The only stable element with an isotope with mass number 11 is boron. Beryllium and carbon also have isotopes with mass number 11, but these are radioactive.
List of radioactive elements?
Elements that decay (give off protons and neutrons) to form other elements. *It's not elements as such that are stable or unstable, but rather isotopes. Even elements of small atomic number have unstable isotopes that undergo radioactive decay, for example carbon-14. Elements with higher atomic numbers than Lead (82) are naturally radioactive in all isotopes. Bismuth (83) has an extremely long half-life, but the time generally becomes shorter (the decay more rapid) as the size of the nucleus gets progressively larger for heavier radioactive elements.
What is the atomic number for radio isotope?
There are radioactive isotopes of all elements, so it depends on what radioisotope you are talking about. For example, carbon has 6 protons, so its atomic number is 6 - whether it is the stable carbon-12, or the radioactive carbon-14.
What is the atomic number of Ar?
That depends on the isotope, as Argon has three different stable isotopes and many different radioactive isotopes.
What element continue to decay until they finally become stable?
All elements above the atomic number of 83 are radioactive, but two elements that are under it are also radioactive. They are technetium (atomic number 43) and promethium (atomic number 61). Radioactive elements are elements that decay until stable. =)
How do isotopes form?
During some radioactive explosion/exposure the atoms combine and if they stay stable they from with extra amounts of protons. Isotopes are when two or more elements have the same number of protons, but different number of neutrons.
Do radioactive elements differ in atomic number?
yes
Are metals radioactive elements?
No. All elements with atomic number greater than 83 are radioactive, including some metals such as polonium, uranium, etc. But there are radioactive isotopes of most metals on the periodic table but are very rare and sometimes must be produced in reactor or particle accelerator.
