Which decay transforms a proton into a neutron, decreasing the atomic number by 1?

Which decay transforms a proton into a neutron, decreasing the atomic number by 1?

• A. Alpha
• B. Beta Minus
• C. Beta Plus
• D. Gamma

Answer: (C)

Beta-plus decay is the process where a proton is converted into a neutron inside the nucleus, causing the atomic number to decrease by one while the mass number stays the same. This happens because the proton transforms into a neutron with the emission of a positron and a neutrino, so the nucleus loses one unit of positive charge but keeps the same count of nucleons. The result is a nucleus with one fewer proton but the same total nucleons. This differs from beta-minus decay (neutron to proton, Z increases), alpha decay (loses two protons and two neutrons, changing Z and A), and gamma decay (no change in Z or A, just energy).

Beta-plus decay is the process where a proton is converted into a neutron inside the nucleus, causing the atomic number to decrease by one while the mass number stays the same. This happens because the proton transforms into a neutron with the emission of a positron and a neutrino, so the nucleus loses one unit of positive charge but keeps the same count of nucleons. The result is a nucleus with one fewer proton but the same total nucleons. This differs from beta-minus decay (neutron to proton, Z increases), alpha decay (loses two protons and two neutrons, changing Z and A), and gamma decay (no change in Z or A, just energy).