MythBusters

[pianolearner]

As homage to one of my favourite TV shows,.

It's a tough job separating truth from urban legend and this thread is intended to confirm, bust or find plausible everything we think we know.


The first one is attributed to timothy42b which is:

Is Glass a solid or liquid?

Busted, Confirmed or Plausible?

I always thought it was a liquid 

[pianistimo]

the fact we have blown-glass factories proves to me it is first a liquid and then a solid.  am i right? 

[donjuan]

It has a melting point!  Depending on the temperature, it could be solid or liquid.
https://www.newton.dep.anl.gov/askasci/chem99/chem99017.htm

see all these melting points:
https://hypertextbook.com/facts/2002/SaiLee.shtml

[Dazzer]

well the same could be said for all elements i think... titanium has a melting point just like water. You could say water is also a solid (its just that we call it ICE but its still water) etc etc

[prometheus]

Solid, liquid and gas(ious) (and plasma) are states of matter. So the question is already flawed, as Donjuan already pointed out.

As for glass being a liquid in room temperature, this idea was totally alien to me until Timothy mentioned some high schools(or whatever level he was referring to) incorrectly teach their students that it is. Why, is totally absurd to me because the properties of glass in room temperature just contradict the notion of what liquid is.

Ok, I used google to find the reason for this myth. Apperently this idea came from people looking at glass windows of very old buildings. The glass was thicker at the bottom. But this had to do with the way glass was constructed in those days.

So this is a very silly urban myth.


I liked the mythbuster episode of the chinese guy that wanted to fly to heaven with a rocket chair. Apperenty he added 42 rockets or something to his chair. Then when the rockets ignited he was never seen of again; he had succeded. He was the first austronaut, or rather taikonaut.

Now when this test was repeated of course no trace of the chair was left. But to say that it got to heaven, nah.

Of course today we do have taikonauts.

[pianolearner]

Solid, liquid and gas(ious) (and plasma) are states of matter. So the question is already flawed, as Donjuan already pointed out.

Why is the question flawed?

Is water a liquid? The answer is 'Yes'. When it's a solid it's not water it is ice and when it is a gas it is steam. So the question, "Is ice a solid or liquid" would be valid.

The materials definition of a glass is a uniform amorphous solid material.

This would make the qualifier "at room temperature" redundant.

Then again, instead of saying water, you could say "steam at room temperature".

[BoliverAllmon]

Solid, liquid and gas(ious) (and plasma) are states of matter. So the question is already flawed, as Donjuan already pointed out.

As for glass being a liquid in room temperature, this idea was totally alien to me until Timothy mentioned some high schools(or whatever level he was referring to) incorrectly teach their students that it is. Why, is totally absurd to me because the properties of glass in room temperature just contradict the notion of what liquid is.

Ok, I used google to find the reason for this myth. Apperently this idea came from people looking at glass windows of very old buildings. The glass was thicker at the bottom. But this had to do with the way glass was constructed in those days.

So this is a very silly urban myth.

I was actually taught this in school. man oh man.

[Kassaa]

Why is the question flawed?

Is water a liquid? The answer is 'Yes'. When it's a solid it's not water it is ice and when it is a gas it is steam. So the question, "Is ice a solid or liquid" would be valid.

The materials definition of a glass is a uniform amorphous solid material.

This would make the qualifier "at room temperature" redundant.

Then again, instead of saying water, you could say "steam at room temperature".

It's all the same thing: H2O, nothing makes a difference in that. Ice and steam are just the names we give them, you don't call molten iron something else than iron do you?

Ice and water are the same, only the molecules are packed more tightly in ice, and they aren't packed together in steam. (Or packed very loose?)

[johnny-boy]

https://math.ucr.edu/home/baez/physics/General/Glass/glass.html

[donjuan]

Why is the question flawed?

Is water a liquid? The answer is 'Yes'. When it's a solid it's not water it is ice and when it is a gas it is steam. So the question, "Is ice a solid or liquid" would be valid.

This would make the qualifier "at room temperature" redundant.

Then again, instead of saying water, you could say "steam at room temperature".

you could just avoid the whole technical issue and say H₂O.  In chemistry, 'Water' is the common name for all states.  for example, in the formation energy chart, it says H₂O_(s) for solid water and H₂O_(l) for liquid water, and H₂O_(g) for steam.  Steam isn't steam at room temperature because the boiling point (point where the vapor pressure equals the pressure of the surroundings) of of H₂O_(l) is 100 deg. Celsius.  If you see steam in a room at 20 deg. celcius (from a coffee pot, for example), well, the reason why you can see it is because it is condensing as the H₂O_(g) loses heat energy to the surrounding air, and turns back into H₂O_(l).

So glass is just the common name for SiO₂.  Asking 'what state is it in" is like asking "how long does it take to drive to work?"  It depends on traffic, just like how the physical state of a material with a melting point depends on temperature (and pressure too, but pragmatically, mostly temperature).  it's so simple, i have no idea why people struggle with this..

[Kassaa]

you could just avoid the whole technical issue and say H₂O.  In chemistry, 'Water' is the common name for all states.  for example, in the formation energy chart, it says H₂O_(s) for solid water and H₂O_(l) for liquid water, and H₂O_(g) for steam.  Steam isn't steam at room temperature because the boiling point (point where the vapor pressure equals the pressure of the surroundings) of of H₂O_(l) is 100 deg. Celsius.  If you see steam in a room at 20 deg. celcius (from a coffee pot, for example), well, the reason why you can see it is because it is condensing as the H₂O_(g) loses heat energy to the surrounding air, and turns back into H₂O_(l).

So glass is just the common name for SiO₂.  Asking 'what state is it in" is like asking "how long does it take to get to work?"  It depends on traffic, just like how the physical state of a material with a melting point depends on temperature (and pressure too, but pragmatically, mostly temperature).  it's so simple, i have no idea why people struggle with this..

We say the same but you say it so much more intelligent .

[prometheus]

Sure, from a philosophical point of view water is not the same as H2O, for example tea is almost a 100% percent H2O, but not the same as water.

But since the question was chemaical, chemical termology needs to be used. Therefore the question is flawed.

[contrapunctus]

Glass is a liquid at room temperature, and it does obey all the properties of liquids. Everything just happens to slowly for us to notice.

I would like o point out thatthere are five known states of matter: solid, liquid, gas, plasma, and degenerate matter.  Degenerate matter is when the atom is so excited that all the electrons are ionized and then crushed back around the nucleus. This is denser than solids, and is seen in pulsars and other extremely dense stars.

[lisztisforkids]

Glass is a liquid at room temperature, and it does obey all the properties of liquids. Everything just happens to slowly for us to notice.

I would like o point out thatthere are five known states of matter: solid, liquid, gas, plasma, and degenerate matter.  Degenerate matter is when the atom is so excited that all the electrons are ionized and then crushed back around the nucleus. This is denser than solids, and is seen in pulsars and other extremely dense stars.

HAHAHAHAHAHAHAHAHA!

[pianolearner]

Sure, from a philosophical point of view water is not the same as H2O, for example tea is almost a 100% percent H2O, but not the same as water.

But since the question was chemaical, chemical termology needs to be used. Therefore the question is flawed.

If it's almost the same then it isn't the same. Philosophical or not, pure water is H₂O (and it does NOT conduct electricity.)

[prometheus]

Uuh, first of you didn't understand the point. Secondly, we now have switched positions? Huh, how can this be? You are now making my argument, while I was making one to explain where your misunderstanding came from.

Yes, if we talk about science water is H2O. But what does the 'word' water mean, what is its definition?

Pure water doesn't exist in nature. If there is a lake filled with water it doesn't mean it's all H2O. There is all kinds of other stuff, either dissolved or not, in the water. The same goes for the water you either buy bottled in the supermarked or which comes out of the tap.

All this water will have small quantities of salts and metals. This does not prevent us from calling it water, eventhough in science we strictly mean H2O.

But let's take this even further. If these small quantities in water are sugars then we stop calling it water. It will be called Lemonade. In the case of tea the apperance will be changed, it will be much less transparent.

But now lets compare different kinds of waters with lemonade and tea. If we take water from a pond the water will be coloured, either brownish or greenish. Very much like tea. But we don't say ponds are filled with tea, they are filled with water.

If we take sea water, this will have a very different taste compared to normal water. The same goes with lemonade. But still sea water is called water.

Now we let a scientist in a lab count how many H2O molecues each of these substances actually contains. If one does that one will still not be able to compute what we call water and what we don't. Some kinds of waters will have much less H2O then some kinds of tea or lemonade, but they are still called water.

This is what I mean with philosophical. This goes back to Aristotle who knew what a chair was but he didn't knew why he knew. So he got as many chairs as he could and lined them up, trying to find some property they all had.

This is not so easy. We construct words without thinking about it, it all works. But when we do think about it we cannot figure it out.

[donjuan]

water is a polar solvent.  It dissolves polar substances -sodium chloride, not beaver feces.. (the K_sp value for that one is pretty low, since most of it remains unaccociated with water, and appears to turn it a shitty brown.)  The reason why you see the 'pond water' as brown, or the lemonade as a bit more transluscent than water, is because they contain particles that are insoluble (or have reduced solubility) in water.  For example, in lemonade, the sugar, the ascorbic acid- these are all highly soluble in water because they have hydroxyl groups that hydrogen bond with H₂O.



look at that!  Each ascorbic acid (Vitamin C) has so many places to hydrogen bond with water!

  But the flakes of lemon, for example, would have more cell wall cellulose, which doesn't dissolve so well in water.  The insoluble particles affect the light transmittance and absorbance values - that is why it looks different.

But whether or not the water is associated with other molecules through H-bonding doesnt change the fact that water is water.  All that philosophical jargin, as interesting as it is, is made obsolete by a few chemistry experiments. 

so when you say,

But now lets compare different kinds of waters with lemonade and tea. If we take water from a pond the water will be coloured, either brownish or greenish. Very much like tea. But we don't say ponds are filled with tea, they are filled with water.

Silence that philosophical voice in your head, and say: "No, pond water is full of insoluble beaver feces, not tea"

 

[prometheus]

Sure, science works.

But this all has nothing to do with what the word 'water' means. It does not mean H2O in every day usage. It would be impossible because we cannot even see if something has enough H2O to be called 'water'.