Sciencemadness Discussion Board
Not logged in [Login ]
Go To Bottom

Printable Version  
Author: Subject: What phenomenon this is?
TmNhRhMgBrSe
Hazard to Others
***




Posts: 112
Registered: 4-7-2019
Member Is Offline


shocked.gif posted on 27-6-2020 at 02:13
What phenomenon this is?


I dissolved KNO3 in room temperature water and filtered. The solution almost saturated. I filtered more solution. This solution is more saturated. When the more saturated solution drop in the not so saturated solution it sink to bottom. I also saw when solution drops into the another solution some rare bubbles formed. The bubbles sink to bottom then break. Some air float back up. What bubbles these are?



sorry for bad english
View user's profile View All Posts By User
mackolol
Hazard to Others
***




Posts: 458
Registered: 26-10-2017
Member Is Offline

Mood: Funky

[*] posted on 27-6-2020 at 02:34


How did you filter it?
View user's profile View All Posts By User
Ubya
International Hazard
*****




Posts: 1232
Registered: 23-11-2017
Location: Rome-Italy
Member Is Offline

Mood: I'm a maddo scientisto!!!

[*] posted on 27-6-2020 at 02:47


the more saturated solution going at the bottom of the less saturated solution is not something strange, a denser solution will stay below a less dense one.
the bubbles? you said "some air floats back up" do you mean that some bubbles are still at the bottom?





---------------------------------------------------------------------
feel free to correct my grammar, or any mistakes i make
---------------------------------------------------------------------
View user's profile View All Posts By User
TmNhRhMgBrSe
Hazard to Others
***




Posts: 112
Registered: 4-7-2019
Member Is Offline


[*] posted on 29-6-2020 at 02:09


I use paper towel to filter.
Solution density I understand. I only dont understand why have bubble sink to bottom. I saw largest bubble diametre about 5mm. When it break has a smaller bubble float back up surface. I guess small bubble is air. The small bubble smaller than 1mm.




sorry for bad english
View user's profile View All Posts By User
B(a)P
International Hazard
*****




Posts: 1114
Registered: 29-9-2019
Member Is Offline

Mood: Festive

[*] posted on 29-6-2020 at 02:49


Quote: Originally posted by CELamCheng  
I dissolved KNO3 in room temperature water and filtered. The solution almost saturated. I filtered more solution. This solution is more saturated. When the more saturated solution drop in the not so saturated solution it sink to bottom. I also saw when solution drops into the another solution some rare bubbles formed. The bubbles sink to bottom then break. Some air float back up. What bubbles these are?


Are you certain that the 'bubbles' are not in part small crystals of KNO3 forming? Dissolved gasses may come out of solution and adhere to the crystals. When the crystals hit the bottom the gas bubble is bumped off and rises to the surface.
View user's profile View All Posts By User
TmNhRhMgBrSe
Hazard to Others
***




Posts: 112
Registered: 4-7-2019
Member Is Offline


[*] posted on 29-6-2020 at 19:47


Not crystals. Bubbles are spheres. I dont think 5mm crystal can through filter lor.



sorry for bad english
View user's profile View All Posts By User
phlogiston
International Hazard
*****




Posts: 1375
Registered: 26-4-2008
Location: Neon Thorium Erbium Lanthanum Neodymium Sulphur
Member Is Offline

Mood: pyrophoric

[*] posted on 30-6-2020 at 14:26


I think you may have observed so-called antibubbles.

Sounds like a joke, but it is not: https://en.wikipedia.org/wiki/Antibubble

Rather than a bubble of air, they consist of a droplet of liquid surrounded by a film of air.
They are easy to make with a soapy solution by allowing drops to fall in a glass of soapy water from a few cm's above the surface. They look very similar to bubbles, but you can recognise them because they float to the surface much more slowly.

The antibubbles you made contain a droplet of concentrated solution, which makes them more dense than the solution they are in. The thin film of air does not provide enough buoyancy, hence they sink rather than float. When they break, the little film of air forms a small regular air bubble that floats to the surface.

Edit: I found a video on youtube with a nice demonstration, showing many aspects of the phenomenon that you also observed: https://www.youtube.com/watch?v=cosjx9fGuPY

[Edited on 30-6-2020 by phlogiston]




-----
"If a rocket goes up, who cares where it comes down, that's not my concern said Wernher von Braun" - Tom Lehrer
View user's profile View All Posts By User
mysteriusbhoice
Hazard to Others
***




Posts: 473
Registered: 27-1-2016
Member Is Offline

Mood: Became chemistry catboy Vtuber Nyaa

[*] posted on 20-7-2020 at 04:37


Quote: Originally posted by CELamCheng  
I dissolved KNO3 in room temperature water and filtered. The solution almost saturated. I filtered more solution. This solution is more saturated. When the more saturated solution drop in the not so saturated solution it sink to bottom. I also saw when solution drops into the another solution some rare bubbles formed. The bubbles sink to bottom then break. Some air float back up. What bubbles these are?


A more saturated solution is denser than less saturated one and hence 1st phenomenon is related to difference in density.
The 2nd one is called an anti bubble where you have a fluid surrounded by air in another fluid and sometimes occurs when dropping one fluid on another in a small stream and can be replicated much more easily and sustained using transducers which sonicate the water.
View user's profile Visit user's homepage View All Posts By User

  Go To Top