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http://filestore.aqa.org.uk/subjects/AQA-PHYA5-1-W-QP-JUN11.PDF
Someone explain how B+ decay goes down 1 left and then 1 right

http://pmt.physicsandmathstutor.com/download/Physics/A-level/Topic-Qs/AQA-Old/Unit-5/Set-A/5.1%20Radioactivity.pdf
Then can someone explain how B- decay goes down 1 left and then 1 right?
Original post by English-help
http://filestore.aqa.org.uk/subjects/AQA-PHYA5-1-W-QP-JUN11.PDF
Someone explain how B+ decay goes down 1 left and then 1 right

http://pmt.physicsandmathstutor.com/download/Physics/A-level/Topic-Qs/AQA-Old/Unit-5/Set-A/5.1%20Radioactivity.pdf
Then can someone explain how B- decay goes down 1 left and then 1 right?


The MS for this is messed up :_:

For Beta+ we remove a proton, add a neutron, and out pops the B+ and ve... this MS shows the opposite, with neutron number decreasing and proton number increasing. I think the typo here is that it should be B- decay...?
Reply 2
Original post by Callicious
The MS for this is messed up :_:

For Beta+ we remove a proton, add a neutron, and out pops the B+ and ve... this MS shows the opposite, with neutron number decreasing and proton number increasing. I think the typo here is that it should be B- decay...?


That's right, the reaction is

ZAXZ1AX+β++νe^A_Z{X} \rightarrow {_{Z-1}^A{X}} + \beta ^+ + \nu _e

for β+\beta ^+ decay, and

ZAXZ+1AX+β+νe^A_Z{X} \rightarrow {_{Z+1}^A{X}} + \beta ^- + \overline{\nu _e}

Where A is the number of neutrons + protons, Z is the number of protons.
Original post by Callicious
The MS for this is messed up :_:

For Beta+ we remove a proton, add a neutron, and out pops the B+ and ve... this MS shows the opposite, with neutron number decreasing and proton number increasing. I think the typo here is that it should be B- decay...?


Original post by Cerdic
That's right, the reaction is

ZAXZ1AX+β++νe^A_Z{X} \rightarrow {_{Z-1}^A{X}} + \beta ^+ + \nu _e

for β+\beta ^+ decay, and

ZAXZ+1AX+β+νe^A_Z{X} \rightarrow {_{Z+1}^A{X}} + \beta ^- + \overline{\nu _e}

Where A is the number of neutrons + protons, Z is the number of protons.

So does B+ go 1 left then 1 up?
Original post by English-help
So does B+ go 1 left then 1 up?


Should, yes
Original post by Callicious
Should, yes

which is the same as electron capture right?
does alpha emission go 2 up 2 right? or 2 down and 2 left?
Original post by English-help
which is the same as electron capture right?
does alpha emission go 2 up 2 right? or 2 down and 2 left?


Alpha reduces proton and neutron number by two each, hence whichever direction does that to the Z and N values :tongue:
Reply 7
Original post by English-help
which is the same as electron capture right?
does alpha emission go 2 up 2 right? or 2 down and 2 left?


Rather than trying to remember each specific case, keep in mind what needs conserving. The conservation rules for this are number of nucleons, and charge. Remember those and you should be able to work out what happens.

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