Kaplan DAT midterm Gchem #9

[plaier]

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9. An atom's atomic mass increased by one as it emits particle. This type of nuclear reaction is an example of

a. alpha- decay
b. beta- decay
c. beta+ decay
d. fusion
e. gamma decay

I picked D,The answer was B
I think that beta- decay can increase number of protons(atomic number), but not the atomic mass. a,c and d also cant increase atomic mass.
That is y I picked fusion. anyway i know that you cannot increase just 1 atomic mass with fusion, but it was the most reasonable answer from those 5 answer choices since fusion is only one that increases mass.

I think this question is totally wrong, am i right?

 

[tranv117]

9. An atom's atomic mass increased by one as it emits particle. This type of nuclear reaction is an example of

a. alpha- decay
b. beta- decay
c. beta+ decay
d. fusion
e. gamma decay

I picked D,The answer was B
I think that beta- decay can increase number of protons(atomic number), but not the atomic mass. a,c and d also cant increase atomic mass.
That is y I picked fusion. anyway i know that you cannot increase just 1 atomic mass with fusion, but it was the most reasonable answer from those 5 answer choices since fusion is only one that increases mass.

I think this question is totally wrong, am i right?

you answered your own question? beta- decay will add a proton, a proton is approximately 1amu so you are increasing the atomic mass. The thing I've noticed is that Kaplan specifies beta - and beta + decays while destroyer and alot of other sources I've seen typically only says beta decay in their questions. When this happens, does anyone know if we should assume that its a beta - or beta + decay?

 

[a1pha]

I ran into this while studying and checked with a grad student at my lab to make sure I wasn't totally off base. It's a typo...just move on.

 

[heatwheat]

you answered your own question? beta- decay will add a proton, a proton is approximately 1amu so you are increasing the atomic mass. The thing I've noticed is that Kaplan specifies beta - and beta + decays while destroyer and alot of other sources I've seen typically only says beta decay in their questions. When this happens, does anyone know if we should assume that its a beta - or beta + decay?

I'm pretty sure we are supposed to assume beta + decay. Someone correct me if I'm wrong.

 

[tranv117]

So i looked up beta decay on wikipedia, and it says that beta decay will change the atomic number by 1 but atomic mass will remain the same. So from the questions, I guess it's wrong?

 

[plaier]

It's not beta+ decay, either.
beta+ decay, u extract positron.
so u add 1 more neutron, but u subtract 1 proton.
therefore, it decrease 1 atomic number, but the mass number is still same.

both beta decays dont change atomic mass number.
I am pretty sure