Manganese has one stable isolope, 15Mn.Part AWhat are the likely decay modes and doughter nuclei for 51Mn ?We expect the 51Mn to decay by beta-minus. The daughter nucleus is 11Cr.We expect the 51Mn to decay by beta-plus. The daughter nucleus is 51Fe.We expect the 51Mn to decay by beta-plus. The daughter nucleus is 51Cr.We expect the 51Mn to decay by beta-minus. The daughter nucleus is 51Fe.Beousat AnswerPart BWhat are the likely decay modes and daughter nuclei for 19Mn ?We expect the 57Mn to decay by beta-minu. The daughter nucleus is 59Fe.We expect the 59Mn to decay by beta-plus. The daughter nucleus is 59Fe.We expect the 59Mn to decay by bota-minus. The daughter nucleus is 59Cr.We expect the 59Mn to decay by beta-plus. The daughter nucleus is 59Cr.
Answer
Decay Modes and Daughter Nuclides of Manganese Isotopes
🔹 Part A: Decay of 50Mn
Manganese-50 (50Mn) has 25 protons and 25 neutrons. Being neutron-deficient, it is proton-rich. Such isotopes typically undergo beta+ decay (positron emission), where a proton converts into a neutron to increase the neutron-to-proton ratio and reach greater nuclear stability.
During beta+ decay, the atomic number decreases by 1 while the mass number stays the same. Hence:
✔ Correct Answer: We expect the 50Mn to decay by beta+ emission. The daughter nucleus is 50Cr.
🔹 Part B: Decay of 54Mn
Manganese-54 (54Mn) has 25 protons and 29 neutrons. It is neutron-rich. Isotopes with excess neutrons usually undergo beta− decay, where a neutron converts into a proton to reduce neutron excess.
During beta− decay, the atomic number increases by 1, but the mass number remains unchanged. Thus:
✔ Correct Answer: We expect the 54Mn to decay by beta− emission. The daughter nucleus is 54Fe.