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Write nuclear reaction equation for β^{−}-decay of `""_83^210"Bi"`.

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#### Solution

α is a nucleus of helium `(""_2^4"He")` and β is an electron (e^{− }for β^{−} and e^{+} for β^{+}). In every α-decay, there is a loss of 2 protons and 4 neutrons. In every β^{+}-decay, there is a loss of 1 proton and a neutrino is emitted from the nucleus. In every β^{−}-decay, there is a gain of 1 proton and an antineutrino is emitted from the nucleus.

For the given case, the various nuclear reaction can be written as:

`""_83^210"B" -> _84^210"PO" + "e"^(-) + bar"v"`

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