Determining the atomic number, mass number, and chemical name during beta decay

AI Thread Summary
During beta decay, the atomic number of Thorium (90) increases by 2, resulting in an atomic number of 92 after two successive decays. The mass number remains unchanged at 233. The correct chemical name for the resulting nucleus is simply "Uranium," without the mass number notation. The confusion arose from misunderstanding the chemical name versus the isotope notation. It's important to recognize that the charge of the nucleus increases due to the emission of beta particles.
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Determining the atomic number, mass number, and chemical name during beta decay!

Homework Statement


The image below shows the element Thorium with the atomic number listed above and a mass number of 233. This element undergoes two successive beta decays. The resulting nucleus will have an atomic number of (1) __________ and a mass number of (2) __________. The chemical name for the nucleus is (3) __________.
(BTW, there was no image shown in the homework, but it can be implied that the the atomic number of Thorium is 90.)


Homework Equations


Thorium (Atomic Number = 90)


The Attempt at a Solution


(1) 92
(2) 233
(3) Uranium-233

I submitted these answers on my homework, but I only got 2/3 correct, meaning one of my answers was wrong. What answer was wrong??
Could it be that #3 should just be Uranium (I'm not sure what a chemical name is...)?
 
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It should be an easy problem to figure out, but I can't find out how to do it! :(
I feel stupid.
 


What kind of Beta Decay is this? There are usually two kinds, where there is a positive emission or a negative emission. That might be where you made your error.
 


Pappers08 said:
What kind of Beta Decay is this? There are usually two kinds, where there is a positive emission or a negative emission. That might be where you made your error.

If it was positive emission then both (1) and (3) would be wrong. So it is negative emission. Maybe the your mistake was that you did not considered that uranium will be charged, since the production of two protons will increase the nucleus charge by 2e and since there is no addition of extra electrons (the electrons from the decay escape from the atom), tha net charge after the decay will be +2e. So, (3) should be ^{233}_{92}U+2
 


It turns out that the correct answer for #3 is "Uranium."
You don't have to add the number at the end.
 


Well I'm glad you fixed the mistake!
 
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