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Unstable Nucleus?: (1 Viewer)

Deadboxes

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Hi guys, I'm currently doing an assignment which is based on the nuclear part of "Production of Metals"
I'm stuck on a question that's a 3 marker.
"Describe the conditions which cause a nucleus to be unstable"
I've written this so far:

Atoms are comprised of both positive, neutral and negative charges, known as protons, neutrons and electrons. In an atoms nucleus, protons and neutrons are found. For an atom to be stable, the positive and negative charges must be the same, for them to cancel out, or in normal terms, there must be the same number of protons and electrons, resulting in a neutral atomic charge. These balanced charges result in a strong electrostatic force which holds the atom together.
However, when atoms have an imbalance in these protons and neutrons, they result in an uneven electrostatic force, causing an unstable state in which the atom’s binding energy isn’t strong enough to hold the nucleus together. To overcome this issue, the unstable atom will lose neutrons and protons in an attempt to become more stable, usually in the form of radiation such as gamma, beta and alpha rays.



What else am I missing?
 
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fan96

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Very large/heavy atoms tend to be unstable. The radioactive elements are only found near the end of the periodic table, where the largest atoms reside - that's no coincidence. The nucleus is too big to keep itself together and will lose particles through radioactive decay.

AFAIK a net positive or negative charge doesn't actually make a nucleus unstable. Sodium ions in aqueous solution have a charge of 1+ and yet they are still stable in that their nucleus isn't breaking up.

Also, I doubt you need to explain to the marker what an atom is and what it's made out of.
 
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Deadboxes

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Very large/heavy atoms tend to be unstable. The radioactive elements are only found near the end of the periodic table, where the largest atoms reside - that's no coincidence. The nucleus is too big to keep itself together and will lose particles through radioactive decay.

AFAIK a net positive or negative charge doesn't actually make a nucleus unstable. Sodium ions in aqueous solution have a charge of 1+ and yet they are still stable in that their nucleus isn't breaking up.

Also, I doubt you need to explain to the marker what an atom is and what it's made out of.
So what conditions actually cause a nucleus to become unstable? I was reading this website and it says that the most stable nucletides have a more or less even number of protons and neutrons.
My marking criteria states:
- Corretly identifies the features that make a nucleus unstable
 

Deadboxes

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My textbook states that Heavy elements with atomic numbers > 80 are stable if the neutron : proton ratio is roughly equal to 1.5:1.
 

Deadboxes

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I've tried to fix it up best I could if anyone could have a look at it and give me feedback that'd be great! :D

Atoms are comprised of both positive, neutral and negative charges, known as protons, neutrons and electrons. In an atoms nucleus, protons and neutrons are found. For an atom to be stable, the positive and negative charges must be the same, for them to cancel out, or in normal terms, there must be the same number of protons and electrons, resulting in a balanced atomic charge. These balanced charges result in a strong electrostatic force which holds the atom together.

However, when atoms have an imbalance in these protons and neutrons, they result in an imbalance in the electrostatic force, causing an unstable state in which the atoms binding energy isn’t strong enough to hold the nucleus together. For heavier elements with atomic numbers greater than 80, their nuclei are stable if the neutron to proton ration is ~ 1.5:1. To overcome this issue, heavy elements (Atomic number > 80) the atoms will lose neutrons and protons to become more stable, usually in the form of radiation such as gamma, beta and alpha rays.
 

same1111

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Conditions in which a nucleus is unstable:
1.There are no stable nuclei with atomic number >83
2. For small atoms stable nuclei have neutron to proton ratios near 1:1, as atomic number increases, stable neutron to proton ratio increases to 1:1.5. This is because a large number of neutrons are required to stabilise repulsion amongst positively charged protons.( If a nucleus lies outside the zone of stability then it can be said to be unstable thats what this is saying essentially.)
 

ichila101

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I've tried to fix it up best I could if anyone could have a look at it and give me feedback that'd be great! :D

Atoms are comprised of both positive, neutral and negative charges, known as protons, neutrons and electrons. In an atoms nucleus, protons and neutrons are found. For an atom to be stable, the positive and negative charges must be the same, for them to cancel out, or in normal terms, there must be the same number of protons and electrons, resulting in a balanced atomic charge. These balanced charges result in a strong electrostatic force which holds the atom together.

However, when atoms have an imbalance in these protons and neutrons, they result in an imbalance in the electrostatic force, causing an unstable state in which the atoms binding energy isn’t strong enough to hold the nucleus together. For heavier elements with atomic numbers greater than 80, their nuclei are stable if the neutron to proton ration is ~ 1.5:1. To overcome this issue, heavy elements (Atomic number > 80) the atoms will lose neutrons and protons to become more stable, usually in the form of radiation such as gamma, beta and alpha rays.
greater than 83 (i.e. any element after bismuth (by textbook definitions for now), as same1111 mentioned) to be more precise. Also if you wanted to be more precise again, the atoms do in fact lose neutrons and protons to become more stable however this is only via beta and alpha radiation gamma radiation but gamma radiation may still be emitted in some cases as extra. Other than that everything looks great
 

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