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Solubility Equilibria Question (1 Viewer)

Carl10101

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Hello, does anyone know a good way to properly structure an answer to this question?

Info: Indigenous Australians detoxify the seeds of cycads, which contain the toxin cycasin. The seeds are crushed to expose the inner kernel and then soaked in water to leach out the water-soluble toxins.

Question: Describe the solubility equilibria of the toxins (4 Marks)

Thanks
 

jazz519

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I don't really remember this stuff that much but like just some things you should do in your answer:

- Describe the fruit or whatever you choose and how the toxins are removed
- Describe in terms of chemistry why the toxin is soluble while the other part of the fruit isn't (this is something you will probably have a better grasp on when you get to module 7 - as there is a large emphasis on things boiling point and solubility there)
- Give an equation if possible
 

Arrowshaft

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Hello, does anyone know a good way to properly structure an answer to this question?

Info: Indigenous Australians detoxify the seeds of cycads, which contain the toxin cycasin. The seeds are crushed to expose the inner kernel and then soaked in water to leach out the water-soluble toxins.

Question: Describe the solubility equilibria of the toxins (4 Marks)

Thanks
Just freshly graduated from chem, but still a bit cooked from the test aha, so I’ll answer it from the top of my head.

the seeds are ground in order to increase surface area to increase the solubility.

also remember the term dynamic equilibrium; this state is reached when the system is closed and no matter can leave or enter the system. Now, when the cycads are leached, this means that they are passed under running water usually from a creek. This means that the solution cannot get saturated to reach dynamic equilibrium - thus it cannot reach a state where the net dissolution is zero since water is continuously flushing out the toxins preventing it from saturating. Hence, when kept under running water for a while the toxins are made more soluble and eventually reach a concentration where the cycasin’s effect on the body is negligible (it doesn’t reach zero however). Also iirc (haven’t done this topic in a while lol) the cycad is pounded and roasted as well after?
 

Carl10101

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Aug 29, 2019
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I don't really remember this stuff that much but like just some things you should do in your answer:

- Describe the fruit or whatever you choose and how the toxins are removed
- Describe in terms of chemistry why the toxin is soluble while the other part of the fruit isn't (this is something you will probably have a better grasp on when you get to module 7 - as there is a large emphasis on things boiling point and solubility there)
- Give an equation if possible
Just freshly graduated from chem, but still a bit cooked from the test aha, so I’ll answer it from the top of my head.

the seeds are ground in order to increase surface area to increase the solubility.

also remember the term dynamic equilibrium; this state is reached when the system is closed and no matter can leave or enter the system. Now, when the cycads are leached, this means that they are passed under running water usually from a creek. This means that the solution cannot get saturated to reach dynamic equilibrium - thus it cannot reach a state where the net dissolution is zero since water is continuously flushing out the toxins preventing it from saturating. Hence, when kept under running water for a while the toxins are made more soluble and eventually reach a concentration where the cycasin’s effect on the body is negligible (it doesn’t reach zero however). Also iirc (haven’t done this topic in a while lol) the cycad is pounded and roasted as well after?
Thanks this was very helpful. Yeah I think they are roasted after the initial process.

Thanks
 

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