THIS USER ASKED 👇

Identify the nuclide produced when plutonium-239 decays by alpha emission: 239 94pu→42he + ? express your answer as an isotope using prescripts. 235 92u submithintsmy answersgive upreview part incorrect; try again; 4 attempts remaining part b identify the nuclide produced when thorium-234 decays by beta emission: 234 90th→ 0−1e + ? express your answer as an isotope using prescripts. submithintsmy answersgive upreview part part c identify the nuclide produced when fluorine-18 decays by positron emission: 18 9f→01e + ? express your answer as an isotope using prescripts. submithintsmy answersgive upreview part part d identify the nuclide produced when thallium-201 decays by electron capture: 201 81tl+ 0−1e→00γ + ? express your answer as an isotope using prescripts.

THIS IS THE BEST ANSWER 👇

1. The answer is ₉₂²³⁵U

Because this is an alpha emission, the atomic number of the daughter nucleus decreases by 2 and the mass of 4 decreases compared to a mother atom. Since 94 is the atomic number of the mother atom the daughter atom should have 94 – 2 = 92 as the atomic number and 239 – 4 = 235 as the mass number.

→Pu → ₂⁴He + ₉₂²³⁵U

2. The answer is ₉₁²³⁴Pa

Because this is a beta emission, a neutron is converted into a proton and an electron is emitted. So atomic number 1 multiplies by mass but mass number remains the same. Accordingly, the atomic number of the atomic daughter should be 90 + 1 = 91 belonging to Pa. But the mass number is the same as 234.

→Th → ₋₁⁰e + ₉₁²³⁴Pa

3. The answer is ₈¹⁸O

Because this is a positron emission, a proton is converted into a neutron as it emits a positron. Thus atomic number 1 decreases by mass compared to mass but mass number remains the same. Hence, the atomic number of the daughter atom should be 9- 1 = 8 relative to O. But the mass number is 18.

₉¹⁸F → ₊₁⁰e + ₈¹⁸O

4. The answer is ₈₀²⁰¹Hg

This is electron capture decay. A proton is converted to a neutron by the emission of a gamma ray. In this process the mass number remains the same as the parent atom which is 201, but the atomic number 1 is reduced to the parent atom. Thus the atomic number of the daughter nucleus is 81 -1 = 80 relative to Hg.

₈₁²⁰¹Tl + ₋₁⁰e → ₀⁰γ + ₈₀²⁰¹Hg