Reef Chemistry Question of the Day 291: Supersaturation

[Randy Holmes-Farley]

Reef Chemistry Question of the Day 291

Here's a thought experiment.

Suppose I take three vials of RO/DI water and add a pure single chemical to each (might be the same or different chemicals or amounts in each vial). They do not seem to dissolve completely with mixing at room temperature, so I heat them up and mix some more. In all cases, the water goes clear as all the solids dissolve.

I let them cool overnight, and get vials that look like the picture below. One is clear (A), one is a little cloudy (B), and one is very cloudy (C).

Which one or two of these solutions is the most likely to be supersaturated when the picture was taken?

Good luck!

Previous Reef Chemistry Question of the Day:

Reef Chemistry Question of the Day 290: Zwitterions

Reef Chemistry Question of the Day 290 Ions can come with a variety of charges on them, including one or more positive charges, one or more negative charges, and some of each. An ion with some of each type is called a zwitterion, In seawater at pH 8.2, which of the following materials exists...

www.reef2reef.com

 

[EeyoreIsMySpiritAnimal]

A.

Edit: I would say "C" but once there is precipitate, isn't the solution now stabilized at "saturation"?

That's why I chose "A", because nothing has precipitated out so the solution might still be supersaturated.

 

[JimWelsh]

Hint: This shows a supersaturated solution of CaCl2 https://www.reef2reef.com/threads/purification-of-cacl2-with-ca-oh-2.228509/#post-2654361

 

[Miami Reef]

B & C

 

[Edgecrusher28]

Going to say A is super saturated to the point it does not all the solution to precipitate. Maybe by raising the temperature it allowed a higher saturation point and then by calling the solution it became super saturated, but literally just guessing. I suppose it make similar sense why water can become supercooled yet remain a liquid, or how with different temps and pressures water can exists in its triple phase.

 

[A Young Reefer]

C

 

[EeyoreIsMySpiritAnimal]

A.

Edit: I would say "C" but once there is precipitate, isn't the solution now stabilized at "saturation"?

That's why I chose "A", because nothing has precipitated out so the solution might still be supersaturated.

e.g. "From a thermodynamic point of view, a supersaturated solution will precipitate solid until it reaches an equilibrium state..."

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.sciencedirect.com/topics/engineering/supersaturated-solution&ved=2ahUKEwiwta_67ZP_AhXckmoFHecGBlEQFnoECCgQAQ&usg=AOvVaw2IJAKCXjblmaXFKCUAjqEA

 

[Randy Holmes-Farley]

e.g. "From a thermodynamic point of view, a supersaturated solution will precipitate solid until it reaches an equilibrium state..."

https://www.google.com/url?sa=t&source=web&rct=j&url=https://www.sciencedirect.com/topics/engineering/supersaturated-solution&ved=2ahUKEwiwta_67ZP_AhXckmoFHecGBlEQFnoECCgQAQ&usg=AOvVaw2IJAKCXjblmaXFKCUAjqEA

Without giving the answer yet, the key to that correct sentence is "will".

 

[redfishbluefish]

Eeny, meeny, miny, moe, ......I'm going with A

 

[Tom.E]

C...just thinking along the lines of O2 supersaturation (pearling)

 

[Miami Reef]

B & C

I’m changing my answer to A.

Since A needed to be heated to dissolve, and did not precipitate out after being cooled, it is supersaturated.

 

[jimk60]

B&C

 

[RedReefer]

C

 

[EeyoreIsMySpiritAnimal]

I’m changing my answer to A.

Since A needed to be heated to dissolve, and did not precipitate out after being cooled, it is supersaturated.

Copy cat

 

[JCOLE]

A

 

[FrugalReefer]

C, because it just is

 

[paragrouper]

WARNING: I am not a scientist.

so, A is for apple, which fell on Issac Newton’s head, so I’m gonna go with A.


what did I win?

 

[Miami Reef]

Copy cat

You’re smart. I can’t argue with that.

 

[EeyoreIsMySpiritAnimal]

You’re smart. I can’t argue with that.

Yeah, smart -a** , lolol!

 

[Miami Reef]

I needed to google what supersaturated was. I’m just a dumb a**, lolol!