Physicists classify matter according to the state of matter, which are gas, liquid and solid. A material is either in one of these states depending on the temperature and/or pressure applied to it. One characterises the state of matter by the mechanical response of a material under pressure.

learn more… | top users | synonyms

7
votes
5answers
102 views

What keeps water molecules in air from falling down?

I was thinking about evaporative cooling, how the particles in water with the most velocity fly out of the water, leaving it colder. But then I thought, how come these water molecules stay in the air ...
3
votes
0answers
72 views

When I dissolve sugar in my cup of tea/coffee, does it become a liquid or gas, or neither? [migrated]

When I dissolve sugar in my cup of tea/coffee, does the sugar go from being a solid to being a liquid or a gas, or neither? Related: What keeps the sugar suspended in the tea?
7
votes
3answers
728 views

Is a plasma necessarily made of monoatomic ions?

Is it possible to have a plasma made of polyatomic ions instead of monoatomic ions? I want to know all the details why such a thing may be attainable or not and, if possible, what methods we can use ...
1
vote
1answer
63 views

(Why) is dumping liquid nitrogen on your head dangerous?

A chemist who dumped liquid nitrogen on his head described the act as very dangerous; yet, at the same time, he mentioned that the Leidenfrost effect would protect him from the dangers of this act. ...
3
votes
0answers
34 views

Quantum description of Raman effect

In the classical description of Raman effect the object of study is the electric polarizability of the system. Since I'm interested in learning the quantum description of the Raman effect and in ...
1
vote
1answer
42 views

Density of Solid States of Compounds

One of the wonderful properties of water (as my high school biology teacher would say) is that in its solid form, it is lighter than its liquid form. This means that when temperatures drop below 0 ...
1
vote
2answers
31 views

Pellet of lithium in a vacuum

What would happen to a grain of sand sized pellet of lithium in a vacuum? Because there is no pressure, would it become more like a sticky liquid?
2
votes
1answer
46 views

Stellar remnants in a state of matter denser than neutron-degenerate

When discussing the stellar life cycle, it's often stated that if the collapsing core of a star is bigger than the mass limit for a stable neutron star, it must collapse to a black hole. However, ...
0
votes
1answer
27 views

How to account for the huge difference in susceptibility of liquid and gaseous oxygen?

I noticed this while studying magnetic fields in matter from Griffiths' Electrodynamics book. A table is provided in the chapter which shows the materials with their respective susceptibilities. Under ...
1
vote
1answer
45 views

Why is supercritical fluid not considered a separate state of matter?

As given on this link, supercritical fluids are viewed more as a continuum which has both liquid and gas properties. This continuum is obtained when a gas is brought to a pressure and a temperature ...
32
votes
6answers
6k views

Why does ice melting not change the water level in a container?

I have read the explanation for this in several textbooks, but I am struggling to understand it via Archimedes' principle. If someone can clarify with a diagram or something so I can understand or a ...
2
votes
3answers
64 views

Doubt about states of matter

What does exactly means "Small molecules may appear as solid, liquid, and gaseous phases without losing their molecular integrity"?, I can't image how just a molecule can be a gas, liquid or solid. ...
5
votes
2answers
505 views

Why can, or can not, a perfectly incompressible fluid exist?

Water is normally assumed to be an incompressible fluid - for example in the context of calculations involving water pressure. I wondered whether that is strictly true, or an approximation? Later I ...
1
vote
1answer
51 views

Do gases have a general upper limit of density?

Is there some limit for the density of gases, at which no change in condition could make it more dense without making it fluid, or solid - or something 'in between'?
0
votes
1answer
97 views

Why is copper a metal?

Context: Solid state physics Question: Can it be reasoned in the context of solid state physics (perhaps within the band theory of solids?) that copper is a metal ?
0
votes
2answers
47 views

Is there an analogue to the role of vapor in liquids and gases, but for solids and liquids?

It seems common for an ordered phase to have some amount of disorder present. For example, the average moment of a ferromagnet is less than maximum except at T=0 due to the presence of fluctuations. ...
4
votes
2answers
338 views

Why does my kettle only make a noise when it is turned on

Almost as soon as I turn my kettle on it starts to make the familiar kettle noise, yet very shortly after turning off the power the boiling noise stops and the kettle is totally silent. The ...
1
vote
1answer
40 views

States of Matter and Equilibrium

Can I say that, matter generally when cooled decreases in volume because, when it is cooled,i.e., we lower the temperature of the surroundings, then the avg. energy of our sample will be higher than ...
7
votes
2answers
183 views

Are there new states of matter at ultrahigh temperatures and densities?

Under extreme energetic conditions, matter undergoes a series of transitions, and atoms break down into their smallest constituent parts. Those parts are elementary particles called quarks and ...
3
votes
3answers
243 views

To which state of matter does the flame belong to?

I had this question from the day(9 years old, now 16) that i learned about states of matter. I have asked so many of my teachers some of them told me gas some as plasma etc. can anyone answer my ...
4
votes
1answer
329 views

Ice bath is always 3C, why?

I've always learned that a mixture of ice and water should reach equilibrium at approximately 0C. I've actually tried to create that a number of times in different contexts and always fail. First, ...
1
vote
1answer
114 views

What is the probability of ice in boiling water?

Ice crystals are spatially ordered, and in every randomness there is a low possibility of temporarily order. If given enough boiling water, and sufficient time, could local clusters water molecules ...
1
vote
1answer
62 views

Triple points for other substances

Can substances other than H2O have a triple point, where the three usual phases of matter (solid/liquid/gas) can exist?
-1
votes
2answers
771 views

Potential energy for different states

While studying thermal physics at school, I have been taught that solids simply have more potential energy than the liquids and gases. Note that it was said that this potential energy is due to the ...
3
votes
1answer
150 views

Why do many books say quasineutrality is needed for a plasma to exist?

Many books on plasma physics (Chen, Goldston, Lieberman) say that quasineutrality must be satisfied for the matter in question to be a plasma. Yet, we know that non-neutral plasmas exist. So why do so ...
2
votes
1answer
143 views

Why does water ($\mathrm{H_2O}$) only have two distinct fluid phases?

Water (and other substances) can exist in many distinct solid phases (with different crystallic micro-structure), but only in two fluid phases - liquid and gaseous, in which the molecules are oriented ...
4
votes
1answer
311 views

What determines a state of matter?

Earlier I studied about the three states of matter-gaseous,liquid ans solid. Then, I came to know about Plasma and Bose-Einstein Condensate. Now, scientists are trying to explain superconductivity as ...
3
votes
2answers
986 views

Why does sweetness of coke change after freezing completely

I freeze my coke in a freezer completely to solid and then keep it out to melt and as it melts portion by portion I starts to drink, initially It will be very sweet and later it wont be sweet at all. ...
0
votes
1answer
433 views

Burning VS Melting: What is the relation in the atomic/molecular structure?

This has never been asked before on this site, so I thought I would ask this to help future searchers, passerbys, or others understand this better. What are the key differences between burning ...
1
vote
2answers
68 views

Microwaves and state of matter

Does the heating efficiency of a microwave oven depend on the state of matter that it heats? If yes, how?
3
votes
4answers
2k views

Can plasma turn back into gas, solid, or liquid?

I wanted to know if, since basic chemistry teaches you that states of matter can be changed, I was wondering particularly about plasma. I know that virtually all of the Sun is plasma, so I was ...
1
vote
2answers
2k views

Why is lightning considered a plasma?

I was wondering why a lightning bolt is coined as "plasma", or a "spark" from an electrical wire/device is as well, yet flares, molten lava, and burning buildings are not(flares are pyrotechnic, ...
2
votes
2answers
150 views

Cloud Microphysics - Does It contain Ice Or Water Or Both?

I'm not sure if this is the right site to post this on but I have a project where I have some cloud microphysical properties: ...
4
votes
1answer
218 views

Speed of sound in non-newtonian fluids

Recently I saw some videos of non-newtonian (shear-thickening) fluids like corn starch mixed with water(sometimes known as oobleck), where the fluid is placed on top of a speaker cone and starts to ...
2
votes
2answers
187 views

Are there critical constants for liquid-solid transition?

I'm aware of the critical constants for gas-liquid transition but is there such constants for liquid-solid transition? Like the maximum temperature above which a liquid cannot be solidified.
2
votes
3answers
480 views

Is a plasma a distinct phase of matter?

Long ago I learned that a plasma was a distinct state of matter after solid, liquid and gas, and also that it was achieved by imparting heat to a the matter. But most references describe a plasma as ...
7
votes
2answers
190 views

How does one calculate where the “surface” of a gas-giant would be?

Okay, so Jupiter, Saturn, et. al are gas giants. I understand that they have large gassy atmospheres, which, due to the pressure would eventually become more and more dense as one approaches the ...
0
votes
1answer
300 views

What is physics behind States of matter?

States of matter in physics are the distinct forms that different phases of matter take on. Four states of matter are observable in everyday life: solid, liquid, gas, and plasma. What is physics ...
1
vote
1answer
4k views

Besides water, which substances are less dense as solids than as liquids?

You can read everywhere about water's extraordinary property of expanding when frozen, thus the reason ice floats on liquid water. What other substances do this? There are claims of mercury, silica, ...
3
votes
3answers
1k views

Is there an inherent difference between solids, liquids, and gases?

I know that at very large scales, solids behave like liquids, which is why planets are round, rather than knobbly. I also understand that you can pour some gases, and, if I have this right, that the ...
4
votes
2answers
687 views

Can a rock be considered frozen

Water usually comes to mind when thinking about freezing. Once it reaches a certain temperature, water freezes, becoming a solid. However could you make the same statement about a rock? Is a rock at ...
18
votes
3answers
4k views

Is play-dough liquid or solid?

At room temperature, play-dough is solid(ish). But if you make a thin strip it cannot just stand up on it's own, so is it still solid? On a more general note, what classifies or differentiates a ...
-10
votes
1answer
183 views

Dry Ice in Liquid States [closed]

If I melt the dry ice in a pool. I am thinking that Can I have bath without getting wet by melted dry ice?
2
votes
1answer
378 views

Why does water have several different solid phase but only one liquid and gas phase

Why does water have several different solid phase but only one liquid and gas phase? Is there any meaning? or any reason behind it? Or is it just the way the nature behaves?
0
votes
0answers
258 views

Triple point temperature and freezing point

Why does the triple point temperature have very similar values to the freezing point, in most substances?
0
votes
1answer
149 views

Identical fermions in the same quantum state

If we are to take two Hydrogen atoms and subject them to the same potential, then wouldn't both Hydrogen atoms be in the same exact quantum state? This bother me because no two identical fermions can ...
2
votes
1answer
113 views

Is the crystallization of a heat pack the same as the crystallization of freezing water?

Is the crystallization of a heat pack the same as the crystallization of freezing water? If so, why does one generate heat where the other does not?
3
votes
1answer
3k views

Is it possible to have a Gas heavier than a liquid?

Does such a pair of substances exist, that in certain physical conditions (temperature, pressure) when both are placed in the same conditions, one will be a liquid, the other - a gas, and the gas ...
5
votes
1answer
8k views

What happens to the temperature of the water when you add salt to a bowl of melting ice?

If you have a bowl of ice that's melting, so the ambient temperature is just above 0 °C, what happens to the temperature of the water when you add salt? I know that the freezing point of salt water ...
3
votes
6answers
5k views

Where on Earth can you find plasma?

Ok, so not that 'where on earth', like literally - 'Where on Earth'. Where on Earth, can you find matter in the 4th state, i.e. the plasma state?