Question
In beta decay, an electron (or a positron) is emitted by a nucleus. Does the remaining atom get oppositely charged?
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Answer
In beta decay, a neutron from the nucleus is converted to a proton releasing an electron and an antineutrino or a proton is converted to a neutron releasing a positron and a neutrino.
$\beta^-\text{decay:}\text{ n}\rightarrow\text{p + e + }\vec{\text{v}}$
$\beta^+\text{decay:}\text{ p}\rightarrow\text{n + e}^+ + \text{v}$
Since the number of valence electrons present in the parent atom do not change, the remaining atom does not get oppositely charged. Instead, due to a change in the atomic number, there's a formation of a new element.
$\beta^-\text{decay:}\text{ n}\rightarrow\text{p + e + }\vec{\text{v}}$
$\beta^+\text{decay:}\text{ p}\rightarrow\text{n + e}^+ + \text{v}$
Since the number of valence electrons present in the parent atom do not change, the remaining atom does not get oppositely charged. Instead, due to a change in the atomic number, there's a formation of a new element.
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