Nuclear stability: PLEASE HELP!!!

[HSCstudent08]

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2002 HSC Q19

Question: Describe the conditions under which a nucleus is unstable

Comments from marking centre

In this part most candidates wrote too much, going well beyond the allcoated space. Many candidates erroneously included electrons in their answer to a question of nuclear stability.

Does that mean i'm wrong if i say this? (read statement below)

... A nucleus is unstable when oxidation or reduction is taking place in the nucleus. This disrupts the outer shell (since it is either gaining or losing electrons) and hence, makes the nucleus unstable.

[brenton1987]

Originally Posted by HSCstudent08

Does that mean i'm wrong if i say this?
... A nucleus is unstable when oxidation or reduction is taking place in the nucleus. This disrupts the outer shell (since it is either gaining or losing electrons) and hence, makes the nucleus unstable.

That is very wrong.
Oxidation and reduction do not occur in the nucleus. Redox processes involve the gain or loss of electrons from the electron cloud. Remember that the cloud surrounds the nucleus but never comes in contact with it. The dissruption to the outer shell results in an ion with more or less electrons compared to the neutral atom. An ion is, depending on the element, a stable entity.

You should have written something along the lines of:
The nucleus contains two types of particle, a positively charged proton which determines the element, and an uncharged neutron which determines the isotope of the element.

A stable nucleus usually satisfies one of two conditions:
1. Protons and neutrons in approximately equal numbers from Z = 1 (hydrogen) up to Z = 20 (Calcium).
2. From Z = 21 (Scandium) to Z = 83 (Bismuth) the ratio of protons to neutrons gradually increases upto approximately 1:1.5.

Thus an unstable nucleus is one which deviates largely from the two conditions above.

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If space remains you may also like to mention that ²H contains a stable nucleus despite a p:n of 1:2.

[Aerath]

And beyond Z = 83, they are all nuclear-ly unstable.

[untouchablecuz]

Originally Posted by HSCstudent08

2002 HSC Q19
... A nucleus is unstable when oxidation or reduction is taking place in the nucleus. This disrupts the outer shell (since it is either gaining or losing electrons) and hence, makes the nucleus unstable.

>_>

[Aquawhite]

Originally Posted by Aerath

And beyond Z = 83, they are all nuclear-ly unstable.

^_^ lol.

[sikhman]

lol redox + instability

[jackydoll]

Originally Posted by HSCstudent08

2002 HSC Q19



Does that mean i'm wrong if i say this? (read statement below)

... A nucleus is unstable when oxidation or reduction is taking place in the nucleus. This disrupts the outer shell (since it is either gaining or losing electrons) and hence, makes the nucleus unstable.

Yes. Yes you are.

Thank you for giving me a wake-up call

Oxidation and reduction have no relation to isotopes.

[blueduck]

Originally Posted by HSCstudent08

... A nucleus is unstable when oxidation or reduction is taking place in the nucleus. This disrupts the outer shell (since it is either gaining or losing electrons) and hence, makes the nucleus unstable.

hun...there are no electrons in the nucleus...but good on u for asking u could have have indirectly caused an examiner to have brain implosion...