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9 Cards in this Set
- Front
- Back
Most naturally occurring isotopes of elements up to atomic number ___ have stable nuclei.
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19
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Elements with atomic numbers of ___ and higher, usually have one or more isotopes that have unstable nuclei.
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20
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What makes an unstable nuclei?
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to many or too few protons compared to the number of neutrons.
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Unstable nuclei are:
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radioactive
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Define radioactive:
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When an unstable nucleus spontaneously emits small particles of energy called radiation, to become more stable.
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radiation takes these forms:
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alpha (α) and beta (β) particles, positrons (β⁺), or pure energy: gamma rays (
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An isotope that emits radiation is called a:
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radioisotope
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For most types of radiation, there is a change in the number of protons in the nucleus. This change is called:
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transmutation
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Transmutation occurs when:
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an atom of one element is converted into an atom of a different element.
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