New answers tagged states-of-matter
Your kettle needs incoming energy from the heating element to turn water in to steam. Steam bubbles forming and collapsing make the familiar sound. Early on many of the steam bubbles don't make it to the top because they cool off when they rise away from the heating element. This is why the familiar rumbling sound starts way before the water boils. The ...
The noise is either from the AC electricity, which would be a 60Hz buzzing, or from small bubbles forming on the heating element itself. When the electricity stops, both the buzzing and the bubble formation will stop as well. Bubbles create sound due to quickly expanding from a small nucleus. Here's a book I found with a section on noise from bubble ...
Flames always contain gas, but often include solid particles as well. Solid carbon particles are responsible for the luminous yellow flames of candles and wood fires. The fraction of the atoms which are ionized (plasma vs gas) is determined by the Saha-Langmuir equation (see J. Appl. Phys. 39, 338 (1968)). There is an equilibrium between ionized and bound ...
No, you should not refer to molecules coming out or going in, unless there is more than one phase (such as in evaporation, sublimation, condensation, etc.). The volume decreases (or increases) because the space between molecules or atoms decreases (or increases), even though the number of molecules or atoms is constant.
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