RE: OK,is Glass a .................. (Full Version)

All Forums >> [Casual Banter] >> Off the Grid



Message

Politesub53 -> RE: OK,is Glass a .................. (10/3/2007 3:28:17 PM)

I explained this on one of the first posts... Its due to the manufacturing process. The glass was cut into triangles and laid thickest edge at the bottom.



camille65 -> RE: OK,is Glass a .................. (10/3/2007 3:48:37 PM)

Okay I just spent a lot of time researching this and I have to now say that glass is neither solid nor liquid.
That glass does NOT flow downward no matter how much time is given to it. Bummer, but I did learn something!



slave2uX -> RE: OK,is Glass a .................. (10/3/2007 4:31:05 PM)


quote:

ORIGINAL: Aneirin

At college today and the usual debate on what glass is,usual answers in that no one will agree so I will ask here.

Is glass a solid or in reality a super cooled liquid?


either way - it is always half full...



RCdc -> RE: OK,is Glass a .................. (10/3/2007 4:43:15 PM)

quote:

ORIGINAL: philosophy
 
..odd, because i have seen the 'thicker at the bottom effect' in really old glass with my own eyes.........


The glass is thicker at the bottom, but it's to do with the beating, cutting and placing, not that it 'sinks' or 'runs'.
 
Peace
the.dark.



RCdc -> RE: OK,is Glass a .................. (10/3/2007 4:44:28 PM)

quote:

ORIGINAL: Politesub53

I explained this on one of the first posts... Its due to the manufacturing process. The glass was cut into triangles and laid thickest edge at the bottom.


ooo bugger, you already have it covered...
More tea my fav polite one?[;)]
 
Peace
the.dark.



Politesub53 -> RE: OK,is Glass a .................. (10/3/2007 4:54:08 PM)

Waves to the dark......I didnt like to interupt you [8D]



BlackKnight -> RE: OK,is Glass a .................. (10/3/2007 5:15:15 PM)

Like I said before:
solids are supercooled liquds, gasses are hyperheated liquids, energy is matter, matter is energy, glass is energy!
addendum:
it's all in your mind, it only exist the way you think it exist, and since your mind doesn't exist nothing exist.



CuriousLord -> RE: OK,is Glass a .................. (10/3/2007 6:04:45 PM)

quote:

ORIGINAL: BlackKnight

Like I said before:
solids are supercooled liquds, gasses are hyperheated liquids, energy is matter, matter is energy, glass is energy!
addendum:
it's all in your mind, it only exist the way you think it exist, and since your mind doesn't exist nothing exist.


Crazy or just an ineffectual sense of humor?



mnottertail -> RE: OK,is Glass a .................. (10/3/2007 6:33:36 PM)

quote:

ORIGINAL: Darcyandthedark

The glass is thicker at the bottom, but it's to do with the beating, cutting and placing, not that it 'sinks' or 'runs'.
 
Peace
the.dark.


This is exactly how it happens for the womenfolk; of course.  Everyone needs to take a lesson from nature. (ignoring age, I suppose............LOL)

Ron the asswhipper



Termyn8or -> RE: OK,is Glass a .................. (10/3/2007 7:44:25 PM)

Darcy..., So are you saying that when they installed the glass they made sure the thicker side was on the bottom ? I know this sounds sarcastic but it is not. This would probably improve the weight distribution, but I never heard of anyone doing it. They just install the glass.

sam...., Good post, but I'll try it in different terms.

Other than solid, liquid and gas, there are other properties of matter. Some of it simply changes viscosity with temperature, and if anyone thinks glass is a good example, try plastic. And if glass does actually flow, it is plastic, but then plastic is used as an adjective, the original usage of the word. (or close)

Some materials are really plastic, and the plastic state of metals is well known to welders. Between what is considered the molten and solid states of pieces of metal there is usually a plastic state. The range of temperature in which this happens varyies based on the alloy of course, but it varies both in range and scope of range. In other words some materials are in the plastic state for only a fifteen degree temperature range, and others are plastric over a one hundred degree range.

Certain specialized welding rods are called eutectic (eutechtic ?) which are used to weld different metals together despit their different thermal expansion coefficients. The word eutectic means that it has a very small range or no plastic state. Otherwise the weld would break as the finished piece cooled.

There is a form of matter in this regard beyond eutectic. Water (calling out an error in an earlier post) is in one state or the other, it is compeletely non-eutectic. In fact water seems to defy physical laws because it actually expands upon freezing, but that is a different issue. Water does not want to change states, in fact right at it's freezing point it's state has alot of hysteresis, which is to resist change basically. It takes more energy to melt water at 31F than it does to get it from 30F to 31F. Once this, one of the clearly definable states of matter, changes, the energy required to raise or lower it's temperature pretty much adheres to it's basic thermal mass. But at that change of states, energy is required, whether to add or remove heat energy.

There is another similar concept relating to the transition between liquid and gas, and is not even the same thing. They make use of this property to bring you air conditioning, which should be called cooling. The boiling and compressing of a liquid through a heat exchanger cools you off. In a refrigeration system, they take advantage of something that is almost the opposite of the behavior of water. Water does not want to change states, freon does. Freon loves to change states, and the same reason you need a shitload of energy to freeze an ice cube is the reason it is not suitable as a refrigerant. Think how easy that would be. In the car, AC leaks, just feed it some water. Not happening because of the propertuies of water. It has like a reverse latant heat.

As you see the full thing, the lines between different states of matter may blur at times. And there is alot more. To say the least, everything dissolves into everything, and there are no exceptions. The process may be slow and undetectable, but it is happening all the time, since time began.

All solids disolve into liquids. All solids dissolve into gases. All liquids dissolve into solids (this is not the same thing as rust), and all solids dissolve into gases.

When you go gas>liquid>solid, the solubility increases with the temperature of the solution.

When you go solid>liquid>gas, the solubility decreases with temperature. I am not sure if this is chiefly the effect of the solution or the solute, but everything is inverted. That is one of those things I have not really explored, but I am aware of the effect.

But it can be true, that some matter is really never solid except at absolute zero. And it is true that some matter will never melt. And there is probably some matter out there that will never become a gas in our lifetime.

Kinda wish Ida studied more, it is fascinating to me.

T



Ponyboy7 -> RE: OK,is Glass a .................. (10/3/2007 8:04:11 PM)

quote:

ORIGINAL: samboct

Hmm- well, I was (well, sorta still am) a chemistry Ph.D.- and to a chemist- solids have long range order.  I will also point out that some solids don't have melting points- they decompose before they melt.  An example would be any thermoset resin, such as an epoxy.  And what I remember about glasses is that they DON'T have a well defined phase transition- it's discontinuous- meaning it leads to hysteresis (actually, I think this is some glasses do, and some glasses don't, but like I said, it's been awhile.)  Here's a made up example of what I'm talking about- Glass A has a glass transition temperature of 550C. Let's start at 700C- where it's a liquid.  So we cool it down to 550C, lo and behold, the material begins to gel and then doesn't move.  Looks like a piece of glass.  Now let's go the other way- let's take the glass and heat it up to 550C.  Why is nothing happening- it still looks like a piece of glass?  Because the temperature isn't sufficient to rupture the bonds of the long range order.  In order to do this- we have to go up to 575C before anything happens.  This isn't a matter of time- you can fully heat glass A to 550C and nothing will happen for years.  Hence there's a hysteresis- things happen differently depending on how they're approached- and this is NOT a well defined phase transition.  A well defined phase transition is from water to ice- happens at 0C and it doesn't matter whether you start with liquid water or ice, you'll get to the same spot no matter how you approach things.  A good definition of a glass is really not easy- the one I remember using was that it was any material that has a glass transition temperature i.e. that hysteresis I just described for glass A.

A crystalline solid is one that does have a sharply defined melting temperature- it's the temperature where the long range order goes away.

DCNovice- I'm assuming your question has been answered- and yeah, the scale is thousands of years to hundreds of thousands of years IIRC.  Put it in more gravity and more heat, and it'll flow faster.

Sam


Hi samboct,

I will point out that long range order is not a requirment for something to be a solid. A solid is said to be crystalline if it has long range order; if a substance lacks long range order, that does not make it a liquid. In point of fact, an amorphous solid is defined as a solid that lacks long range order.

quote:

 This isn't a matter of time- you can fully heat glass A to 550C and nothing will happen for years


This is completely incorrect; if you recall from thermodynamics, the glass transition temperature is time dependent (hence the "time-temperature superposition principle" for glasses); time dependency is one of the important qualities of a glass transition temperature, so, heating the glass to 550 degrees very likely could produce a transition given a sufficient time scale, or heating rate since glass transition temperatures are also rate dependent. One must specify the rate at which the heating occurs, and its frequency.  It is for that reason that some do not consider glasses to have a well defined phase transition.

quote:

Because the temperature isn't sufficient to rupture the bonds of the long range order


This is incorrect; amorphous solids, such as glass, do not have long range order. Recall that amorphous solids are characterized by a topological disorder, so no long range order exists in their structure Thus, glass has short range order, but it does not have long range order like crystalline solids, so there is no long range order to break. Perhaps you are referring to symmetry breaking? Symmetry breaking does occur, but not in the same sense as in crystals.



Politesub53 -> RE: OK,is Glass a .................. (10/4/2007 1:14:18 AM)

Hi Termyn8or..... Here is a link for you, the last paragraph explains things. I dont think there was any reason for the thick edge being at the bottom, although it seems more logical to do it that way.

http://www.sciam.com/article.cfm?chanID=sa018&articleID=EB5F29F9-E7F2-99DF-3AEAF645B66DB532



Real0ne -> RE: OK,is Glass a .................. (10/4/2007 1:26:22 AM)



So then if you wear glasses after a few years everyone looks like a fat ass?



CuriousLord -> RE: OK,is Glass a .................. (10/4/2007 1:34:51 AM)

Correct.
Assuming that the obesity trend keeps up.



happyplayer06 -> RE: OK,is Glass a .................. (10/4/2007 3:15:33 AM)

I can't believe this thread, people who have no idea are posting and people who obviously do have an idea are failing to communicate it.

The thing with glass is that there is no clear transition from solid to liquid. We have heard this earlier but it was kind of hidden in mumbo jumbo.

There are other amorphous solids besides the glass we all have in our windows. Toffee is one. If you think of a piece of toffee it is hard and brittle when you take it out of the packet (assuming you are not in the tropics or killing the planet with your central heating). If you suck it (and I know you do) it gets soft and flexible. Unfortunately for the example it then dissolves, but if you were to heat it in a pan it would progessively get softer until it flowed under its own weight. You might get it to boil if you are careful but soon the sugar would begin to decompose, it would burn onto the pan.

Glass is the same (except for the burning part), it just gets softer until we decide that it is flowing and we say it is a liquid. Compare this with ice, if you heat it, it warms up until it begins to melt and you have a pool of liquid at the freezing (melting) temperature and a block of ice also at its freezing (melting) temperature. You can not heat water over 0degC if it has  a block of ice in it. Well you can but not much because water isn't a perfect conductor, but you sure can't boil it. It doesn't matter how much you heat the ice it always stays brittle. If you have a block of ice from the freezer it will absorb heat (energy) from the room, warm up to its melting temperature and then remain at that temperature while it absorbs enough energy to transform into a liquid. Glass and toffee have a fairly constant temperature change as they absorb energy and we arbitrarily decide they are runny enough to call them liquid. Ice hardly gets softer as it warms up (you cant tell but it can be measured) then it suddenly begins to flow. Glasses (including toffee) just get weaker until they begin to flow.

A super cooled liquid is a liquid cooled below its equilibrium melting (freezing) point. It is not a solid. You can do this with water but it has to be pure and you need a snazzy thermometer. The water will stay a liquid until a seed crystal forms or is introduced and then rapidly freeze. Sodium acetate is a salt that freezes at about 50degC (which is warm) it can be supercooled as a liquid to below room temperature. You may have seen it sold in vinyl bags as a heat pad. There is a little clicky thing in the bag. When you click it a seed crystal is formed and the contents begin to rapidly solidify, releasing the latent heat of crystalisation, the whole thing warms up to about 50degC which is really nifty if you have cold fingers or menthol rub on your pink bits. 50degC is actually its freezing temperature and once crystalization is initiated it begins to become a solid at its freezing temperature and continues to freeze as fast as it can give up its latent heat of crystalization. After that it is all solid and it eventually cools down to room temperature again. Then you microwave it or put it in a pot of boiling water until it melts, when it cools it stays a supercooled liquid until crystalization is initiated by the clicky thing.

Somebody flog that guy who started wanking on about eutectics. A eutectic is a mixture of two (or more) components that has the lowest melting point. If you mix Copper and Zinc you produce Brass. Brass melts at a temperature below either Copper or Zinc. There is a specific ratio (I am too lazy to look it up) that has the lowest melting point. This is the eutectic mix and the eutectic temperature. If you have molten alloy that is not the eutectic mix the first crystals that form have a different composition to the liquid (it is a wonderful universe, don't knock it, distilation relies on the same principle for the vapor liquid transition and if it didn't work there'd be no hard liquor). The cool part of alloys is that because the solid that forms first has a different composition to the remaining liquid the composition of the liquid changes and so does the freezing point (it gets lower) so the alloy has a solidification range. As it cools it goes gritty then pasty then hard. This is different to a blacksmith heating steel to forge it. It is what happens when you cast metal in a mold. Check out the grainy surface on broken metal things. Panel beaters used to use a special solder before plastic body fillers,were invented. It was a lead zinc alloy far from the Eutecic composition, it had a wide solidifiation range that let it stick to vertical surfaces and be shaped as it cooled. Some hot rods are still called lead sleds.
Eutectic welding rods melt at a lower temperature than the parent material that is being welded and there is some other cool effect involving not messing up the alloy structure in the heat affected zone next to the weld.

Fuck I'm clever, just ask me



chellekitty -> RE: OK,is Glass a .................. (10/4/2007 3:23:17 AM)

now i am even more confused, are you with the glass is a liquid or the glass is a solid crowd? because all you did was explain the process of changing a solid to a liquid and prove the glass is a solid crowd...so if thats what you were going for...thanks....

edited to add: i had to argue with someone who wanted to tell me that milk was a solid a couple of weeks ago...



breatheasone -> RE: OK,is Glass a .................. (10/4/2007 3:29:24 AM)

quote:

edited to add: i had to argue with someone who wanted to tell me that milk was a solid a couple of weeks ago...

HOLY CRAP!...sounds like they need a knew refrigerator!![:D]



breatheasone -> RE: OK,is Glass a .................. (10/4/2007 3:33:53 AM)

quote:

ORIGINAL: Aneirin

At college today and the usual debate on what glass is,usual answers in that no one will agree so I will ask here.

Is glass a solid or in reality a super cooled liquid?

Solid...if it was indeed a "super cooled" liquid it would need that to maintain the solidity?...but it doesnt...it maintains its solidness at room temp. just mho



RCdc -> RE: OK,is Glass a .................. (10/4/2007 3:58:21 AM)

quote:

ORIGINAL: Termyn8or

Darcy..., So are you saying that when they installed the glass they made sure the thicker side was on the bottom ? I know this sounds sarcastic but it is not. This would probably improve the weight distribution, but I never heard of anyone doing it. They just install the glass.

T


Hello T (it's .dark. post btw, not Darcy)
 
We aren't speaking about modern day glass which tends to be more uniform, but that which was constructed hundreds of years ago - mostly medieval times - by 'hand' blown in cylinders then flattened afterwards - and not mass produced like todays standards.  It is thicker at one place due to the weight distribution of the cylinder and I have seen various examples of why, due to weight distribution or to the way they made the frames or even to assist 'run off' from rain water (it meant that water had less place to collect so the frames didnt rot as quick) - but the urban legend was that the glass had 'sunk' to the bottom so that must mean that glass is a fluid.  However that isn't the case as it was to do with installing the glass not that glass is a fluid.
(I'm not posting links coz Polites already rocking at doing that - but I will if you really need them)
 
Peace
the.dark.



Marc2b -> RE: OK,is Glass a .................. (10/4/2007 7:08:58 AM)

Aileen68 said:
quote:

It's a container meant to be frosted with really cold beer in it.

No! Do not frost your beer mugs! It dilutes the flavor of the beer (I’m really proud of the fact that I knew this before that Samuel Adams commercial came out).

FullCircle said:
quote:

Glass is Chinese for grass IMHO.

Wait a minute! I just realized! That Chinese guy wasn’t asking me to help him install a window! He was asking me If I wanted to get high!  [sm=ofcourse.gif]

Philosophy said:
quote:

..odd, because i have seen the 'thicker at the bottom effect' in really old glass with my own eyes.........

Me too. It definitely looked like it was flowing, albeit, at a rate that would make a snail look like it was traveling at warp speed.

I was taught that glass is a liquid but that it viscosity (rate of flow) is so low that we can use it as a solid. Maybe science has learned otherwise since then. Whatever... as long as my glass holds my wine, I’m not complaining. As for old cathedrals, I read somewhere that the glass in the windows was mixed with lead precisely to keep it from flowing.



Page: <<   < prev  1 2 [3] 4   next >   >>

Valid CSS!




Collarchat.com © 2025
Terms of Service Privacy Policy Spam Policy
0.03125