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Do water molecules carry watches?If not, how do they know if they have been heated quickly?If they don't know, then how can they act differently?
On the other hand, in microwave superheating, the boiling can occur long after the heater is turned off, and the water is moved away from the microwave.
Anti-Bumping GranulesIn Safeguards in the School Laboratory (11th edition), section 6.2 we state:"The avoidance of ?bumping? can be achieved by the addition of pieces of broken pot or special anti-bumping granules, which promote smooth boiling. Anti-bumping material should only be added to a cold liquid. If there is a need to add it to a liquid that has already been heated, the liquid should be removed from the heat and allowed to cool for several minutes, otherwise it may boil over.''A letter received from a member provides a dramatic illustration of the necessity for this advice:"During a class distillation of an ethanol/water mixture the teacher in charge realised that the pupils had not added anti-bumping granules. He asked the pupils to stop heating and remove the bungs from the flasks. On adding granules to two of the flasks violent boiling occurred and hot ethanol was thrown out, to a height of one metre or more. The ethanol on the bench was then ignited by a bunsen burner ...... "
Did you think your post made sense?Don't you understand what this means?
Blindly accepting authoritative texts is not understanding.
Refusing to accept the testimony of someone who worked in a lab for 30 years or so is also "not understanding" reality.
Testimonies have lower scientific value than experimental results.
I don't know the details of your experience.
I told you the observations and you asked for documentation. I provide documentation, and you say I shouldn't accept it.
Quote from: hamdani yusuf on 21/12/2023 13:03:06Testimonies have lower scientific value than experimental results.You have just tried to tell us that the observations made by a scientist in a laboratory have less value than the observations made by a scientist in a laboratory.
Quote from: hamdani yusuf on 21/12/2023 13:03:06 I don't know the details of your experience.That's OK, because I do.
The fact that you, on a few occasions, did not see it doesn't change that, does it?
Quote from: Bored chemist on 21/12/2023 13:08:40Quote from: hamdani yusuf on 21/12/2023 13:03:06Testimonies have lower scientific value than experimental results.You have just tried to tell us that the observations made by a scientist in a laboratory have less value than the observations made by a scientist in a laboratory.How can I know that you didn't lie or being mistaken?
There must be something that caused the difference. Which so far hasn't been identified.
The only big difference is that the temperature gradients are typically less steep..
//www.youtube.com/watch?v=ceifHU0wX-UHere's another video trying to explain superheated water by microwave. It says that water can become hotter than its boiling point without actually boiling. Unfortunately, it's not demonstrated in the video, since the thermometer only show 208?F, instead of a number larger than 212?F.
Quote from: hamdani yusuf on 21/12/2023 13:49:16Quote from: Bored chemist on 21/12/2023 13:08:40Quote from: hamdani yusuf on 21/12/2023 13:03:06Testimonies have lower scientific value than experimental results.You have just tried to tell us that the observations made by a scientist in a laboratory have less value than the observations made by a scientist in a laboratory.How can I know that you didn't lie or being mistaken? You can't.But that's equally true whether I'm being a scientist or being a scientist.Why would it be more trustworthy if I was a scientist rather than a scientist?Your PoV makes no sense.It's still me.
Infrared thermometer has its own challenges, since it's affected by emmissivity of the surface.
https://www.animations.physics.unsw.edu.au/jw/superheating.htmWhy does it occur to a greater degree in microwave ovens than in saucepans or kettles?In a microwave oven, the water is usually hotter than the container, whereas parts of the kettle or saucepan are usually hotter than the water. Further, the surfaces of some containers used in microwave ovens may be very smooth, almost at a molecular scale, whereas this is not true for kettles or saucepans.Microwave ovens heat the water directly: the microwaves pass through the container and the water, and the water itself absorbs energy from them. The container absorbs little energy directly. In a kettle or saucepan, the container itself (saucepan) or a heating element (some kettles) is hotter than the water. The hottest points cause a small amount of local superheating, boiling is initiated here, and this then stirs the water.