How is Nuclear Stability Related to the Band of Stability and the Neutron to Proton Ratio

An isotope's stability depends on where its neutron-to-proton ratio falls on the band of stability and the existence of certain magic numbers.

What are stable isotopes? Stable isotopes are those that do not undergo radioactive decay. The neutron-to-proton ratio of these isotopes fall on the band of stability.

Isotopes whose neutron-to-proton ratio do not fall on the band of stability, on the other hand, are unstable, and therefore radioactive.

This is generally the case when an isotope's atomic number, number of protons, is greater than 83. Large isotopes tend to decay by alpha radiation, because massive alpha particles are given off.

Lighter isotopes whose neutron-to-proton ratios do not fall on the band of stability will also be radioactive. If an isotope's neutron-to-proton ratio falls to the left of the band of stability, meaning that it has too many neutrons for its number of protons, it will tend to undergo beta decay, in which a beta particle is emitted, decreasing the number of neutrons while increasing the number of protons. If an isotope's neutron-to-proton ratio falls to the right of the band of stability, meaning that it has too few neutrons for its number of protons, it will tend to undergo positron emission, in which a positron is emitted, increasing the number of neutrons while decreasing the number of protons.

In this chemistry lesson, you will learn:
 why some isotopes are radioactive
 why isotopes decay
 how to determine the neutron-to-proton ratio of an isotope
 how to identify the most stable isotope by comparing its neutron-to-proton ratio to the band of stability
 which type of decay a radioactive isotope will undergo, depending on its neutron-to-proton ratio and where it falls on the band of stability
 how magic numbers of protons and neutrons help predict the stability of an isotope
 The 3-step checklist for predicting the stability of an isotope

And solve these sample problems:
 Determine the neutron-to-proton ratio of C-12, C-13 and C-14, and identify the most stable isotope.
 Is Mn-54 Stable?
 Write the equation for the probable mode of decay of Aluminum-28.

You can learn more about the neutron-to-proton ratio and the band of stability definition by visiting:

To learn more about alpha, beta and gamma decay, watch my video here:

This video is created by an experienced Chemistry teacher for high school students who are looking to learn more about nuclear stability, the neutron-to-proton ratio, and the band of stability.

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how is nuclear stability related to the neutron-proton ratio
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[banny]

Thanks professor no words to describe your help to me ur are awesome

[biodhave]

One word for you. "You are AWESOME"

[Kreller]

How could you possibly have anything other than a positive number of either protons or electrons. You clearly said 'positive' numbers when you meant 'even'. You should correct that or give a warning to listeners. Otherwise, useful video. Thanks

[elenaolivares]

How is the energy of space motion (Pure motion) translated to the atom.??? How can the equilibrium of the atom be disturbed to produce mass motion.

[kpoplover]

Wait, I thought that since 54-Mn had a neutron to proton ratio of 1.16, that since it wasn't a 1.5 to 1 ratio, it wouldn't be considered stable? And how would this method of checking the N/Z ratio work if you aren't given the band of stability to check with?

[OffWithReligion]

the beta particle that was emitted has a value of -1 e-? So the Silicon is not positively charged, and remains neutral?