Solved: Radioactive Decay Equations, Identify Type of Decay

[ProPatto16]

Homework Statement

Complete the following decay equations by inserting the missing particle or nuclide information. Identify each type of decay.

i) ⁹⁰_?Sr = ^?₃₉Y + ? + ?

ii) ²²_?Na = ^?_?Ne + β⁺ + ? + energy

iii)²⁴²₉₄Pu = ^?_?? + alpha + ?

iv) ²³⁵_?U = ⁹¹_?Sr + ¹⁴¹_?Xe + ?

v) ⁰_-1e + ⁰₊₁e → ?

The Attempt at a Solution

i) ⁹⁰₃₈Sr = ⁸⁹₃₉Y + β^- + ? this is beta decay.
- note, lost 1 nucleon. is this ? just ¹n?

ii) ²²₁₁Na = ²⁰₁₀Ne + β⁺ + ? + energy also beta decay
- note, lost 2 nucleons. is this ? just 2¹n?

iii) ²⁴²₉₄Pu = ²³⁸₉₂U + alpha + ? alpha decay

iv) ²³⁵₉₂U = ⁹¹₃₈Sr + ¹⁴¹₅₄Xe + ? fission?

v) i have no idea.

- Just looking at that, there seems to be an extra ? for each decay equation. in my text throughout there's only the decay pronumeral in the products, not something extra as well. so I am not really sure what is meant to go in there?
- Also I am not sure about the relevance of the energy is ii) since all of these decays emit energy anyway.
- iv) doesn't look to be any kind of decay, it seems to represent fission. which would make that '?' 3¹n?
- and v) i have no idea what the result of an electron positron bond is.

 

[mikelepore]

v) Matter and antimatter combining to result in something that, according to the superscript and subscript, will have no mass and no charge. That tells us what comes out of it.

 

[ProPatto16]

ohhh... becomes 2 neutrinos where a neutrino is a particle with no charge and mass equal to an electron?... that would conserve mass and charge...

and your not sure about the other '?' either?

 

[ProPatto16]

stumpedddd

 

[ProPatto16]

...

just so my thread goes to the top of the list again so more people see it. haha