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AQA alevel physics qs

http://physicsloreto.weebly.com/uploads/1/4/8/5/14853288/nuclear_questions_2017-18.pdf

The extended writing question 1.

Do we need to familiarise ourselves with the elements mass numbers?
Reply 1
Original post by 2022 g
http://physicsloreto.weebly.com/uploads/1/4/8/5/14853288/nuclear_questions_2017-18.pdf

The extended writing question 1.

Do we need to familiarise ourselves with the elements mass numbers?


You'd be expected to know about hydrogen and helium, but you should be told any others if they are important for a question. It's just the concept you need to understand rather than memorising a lot of values.
Reply 2
Original post by Pangol
You'd be expected to know about hydrogen and helium, but you should be told any others if they are important for a question. It's just the concept you need to understand rather than memorising a lot of values.

Ok good. Cause the question didn’t give any values for the mass numbers of the elements. Ik that hydrogen and helium should already be known. But the mass number isn’t given for Po (polonium). Which is why i was wondering if you had to memorise certain elements. And for the question it is important to know the mass number. In order to form the decay equation
So in the exam we would be given these values then i assume?
(edited 1 year ago)
Reply 3
Original post by 2022 g
Ok good. Cause the question didn’t give any values for the mass numbers of the elements. Ik that hydrogen and helium should already be known. But the mass number isn’t given for Po (polonium). Which is why i was wondering if you had to memorise certain elements. And for the question it is important to know the mass number. In order to form the decay equation
So in the exam we would be given these values then i assume?

Do you have to know the mass number for polonium to answer that question? You can work it out via the decays.

In any case, many elements have many isotopes, so there is no one answer to what their mass numbers are.
Reply 4
Original post by Pangol
Do you have to know the mass number for polonium to answer that question? You can work it out via the decays.

In any case, many elements have many isotopes, so there is no one answer to what their mass numbers are.


I dont think its possible.
I know how to get the answer if the mass number is given. Its just a guessing game really. Cause the element can go through either one or more decays.And to form the equation you need to know the mass number.
Reply 5
Original post by 2022 g
I dont think its possible.
I know how to get the answer if the mass number is given. Its just a guessing game really. Cause the element can go through either one or more decays.And to form the equation you need to know the mass number.

It is possible, and you don't need to know any mass numbers.

If you start with the Bi-212 that they give you, the only way you can get polonium is via beta minus decay. If you balance the equation that goes with this, there is only one mass number you can get for the polonium.
Reply 6
Original post by Pangol
It is possible, and you don't need to know any mass numbers.

If you start with the Bi-212 that they give you, the only way you can get polonium is via beta minus decay. If you balance the equation that goes with this, there is only one mass number you can get for the polonium.

Wait no i see your point. My bad.
Thank youu!
Reply 7
Original post by Pangol
It is possible, and you don't need to know any mass numbers.

If you start with the Bi-212 that they give you, the only way you can get polonium is via beta minus decay. If you balance the equation that goes with this, there is only one mass number you can get for the polonium.

Wait couldn’t you get multiple combinations. So like 1 alpha and two betas, as well as just 1 beta, for Bi-212 decaying to Po?
So you would kinda need to know the mass number then right?
(edited 1 year ago)
Reply 8
Original post by 2022 g
Wait couldn’t you get multiple combinations. So like 1 alpha and two betas, as well as just 1 beta, for Bi-212 decaying to Po?
So you would kinda need to know the mass number then right?

The question tells you that there is either one alpha followed by one beta minus, or one beta minus followed by one alpha.
Reply 9
Original post by Pangol
The question tells you that there is either one alpha followed by one beta minus, or one beta minus followed by one alpha.

Oh wait i read “one or more” in the wrong context.
Ty again bro.

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