why are some isotopes radioactive?
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Many elements have one or more isotopes that are radioactive. These isotopes are called radioisotopes. Their nuclei are unstable, so they break down, or decay, and emit radiation. ... A: The nucleus may be unstable because it has too many protons or an unstable ratio of protons to neutrons.
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Isotopes are atoms of the same element that have different numbers of neutrons but the same number of protons and electrons. The difference in the number of neutrons between the various isotopes of an element means that the various isotopes have different masses.
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Isotopes are forms of an element that have the same number of protons but different numbers of neutrons.
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Like other elements, uranium occurs in several slightly differing forms known as 'isotopes'. ... The isotope U-235 is important because under certain conditions it can readily be split, yielding a lot of energy. It is therefore said to be 'fissile' and we use the expression 'nuclear fission'.
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The only radioactive materials that glow are radium (which is why it used to be used for fluorescent paint) and certain types of extremely powerful plutonium isotopes.
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Atoms found in nature are either stable or unstable. An atom is stable if the forces among the particles that makeup the nucleus are balanced. An atom is unstable (radioactive) if these forces are unbalanced; if the nucleus has an excess of internal energy.
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All elements with atomic numbers greater than 83 are radioisotopes meaning that these elements have unstable nuclei and are radioactive. Elements with atomic numbers of 83 and less, have isotopes (stable nucleus) and most have at least one radioisotope (unstable nucleus).
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Isotopes of uranium. Uranium (92U) is a naturally occurring radioactive element that has no stable isotope. ... All three isotopes are radioactive (i.e., they are radioisotopes), and the most abundant and stable is uranium-238, with a half-life of 4.4683×109 years (close to the age of the Earth).
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Explanation: Isotopes of an element are atoms of the same element with same number of protons but different number of neutrons.
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The reason that dinosaur fossils can be radioactive is because they come from the ground, and radioactive elements are a common component of soils and rock formations all over the earth. In fact, 50 – 80% percent of the heat warming the earth's core is created by the decay of radioactive elements.
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The reason that dinosaur fossils can be radioactive is because they come from the ground, and radioactive elements are a common component of soils and rock formations all over the earth. ... Also, fossils preserved in areas like these can be radioactive themselves.
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Isotopes are atoms of the same element that contain an identical number of protons, but a different number of neutrons.
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As we have seen, radioactive decay is a property of a particular nucleus. In comparison, radiation is a possible consequence of many processes, not just radioactivity. ... ionising radiation: radiation that can remove an electron from its orbital. neutrons: free neutron particles that can collide with other atoms.
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In an unstable atom, the nucleus changes by giving off a neutron to get back to a balanced state. As the unstable nucleus changes, it gives off radiation and is said to be radioactive.
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The number of neutrons is variable, resulting in isotopes, which are different forms of the same atom that vary only in the number of neutrons they possess. Together, the number of protons and the number of neutrons determine an element's mass number.
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Which means it's no longer carbon because carbon atoms always have six protons. ... With 92 protons and upwards of 140 neutrons, uranium atoms are massive. And no isotopes of uranium are stable — they're all radioactive.
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Isotopes are different forms of the same element. Different isotopes have different numbers of neutrons. Neutrons do not carry an electric charge, so the number of neutrons in an atom does not affect its electric charge.