Concept:Beta positive (\(\beta^{+}\)) decay, also known as positron emission, involves a proton transforming into a neutron.
Formula:$$ _{1}^{1}\text{p} \rightarrow _{0}^{1}\text{n} + _{+1}^{0}\text{e} + \nu_e $$
Solution:- Because one proton is lost but exactly one neutron is instantly created, the total count of nucleons (protons + neutrons) inside the nucleus does not change.
- Therefore, the mass number (nucleon number, \(A\)) is strictly conserved.
- Note: This conservation of mass number holds true for all forms of beta decay (beta-plus, beta-minus, and electron capture).
Why other options are incorrect:Option B violates the fundamental conservation laws of nuclear physics. Options C and D do not grammatically answer the status of a numerical quantity.
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