The three states of matter... or four ?

[Perfection]

Hm? If so, my chemistry textbooks lied to me.

Liquid carbon is a major pain to create, but it can be done take a look at the phase diagram to see why... http://en.wikipedia.org/wiki/Image:Carbon_basic_phase_diagram.png


Liquid CO2 is really easy to make, though. You just need a high pressure environment.

Edit: Whoops, it's high pressure, silly me.

 

[nonconformist]

That seems pretty vague to me. For instance, glass could be said to be a liquid, because it does flow, only very slowly : very old glass, such as found in churches, is thicker at the bottom than at the top.
So at an instant T, glass could be said to be a solid, but over a very long time, it behaves like a liquid.

Glass is by technicality a liquid, but it's jsut easier to refer to it as a solid in day-to-day use.

 

[Chieftess]

I din't learn till High School but Plasma (not the blood plasma but rather the stuff in the sun) is indeed the 4th element
..It's logical to skip that in grammer school I suppose (Iam not saying or assuming that your in grammer school )

The same with negative numbers.

Plasma is the 4th state (learned that in 4th grade), but there's also 2 more, according to a recent article (can't find it...) that says there's 2 more at near absolute zero. (Something that has to do with how the atoms are polarized/aligned or whatnot).

 

[ainwood]

Here is the phase diagram for water:

Note the critical point (C) - at pressures and temperatures above this, there is a pseudo-fourth-phase, called 'dense phase'. You can't really distinguish dense-phase to be different from liquid or vapour, so its called 'dense phase' - in basic terms, it has the properties of a vapour but the density of a liquid.

 

[SomethingWitty]

That seems pretty vague to me. For instance, glass could be said to be a liquid, because it does flow, only very slowly : very old glass, such as found in churches, is thicker at the bottom than at the top.
So at an instant T, glass could be said to be a solid, but over a very long time, it behaves like a liquid.

That's actually a myth. The glass is thicker at the bottom due to old glassmaking methods, not because it's actually flowing.

Some materials scientists worked it out and figured it would take millions of years for glass to distort like that on its own.

For all practical purposes glass is a solid. An amorphous solid, sure, but a solid none the less. If you put it in a container it does not take the shape of the container.

Now that said, the "phases of matter" aren't written in stone. Like I mentioned above, there are many substances that have properties of several states of matter and cannot be placed in an specific category- sand, ketchup, helium-3, etc.

 

[SomethingWitty]

Liquid CO2 is really easy to make, though. You just need a low pressure environment.

High pressure. In fact, that's how they dissolve the caffeine out of coffee beens to make decaffeinated coffee.

 

[nonconformist]

To evapourate, water needs impurities in it, does it not?
I.E, you can super-heat it?

 

[Perfection]

High pressure. In fact, that's how they dissolve the caffeine out of coffee beens to make decaffeinated coffee.

Whoops, yep, High Pressure.

 

[SomethingWitty]

To evapourate, water needs impurities in it, does it not?
I.E, you can super-heat it?

No, water evaporates just fine on its own.

It is possible to superheat water if you've got a nice smooth container and a suited heating source- like a microwave oven.

 

[The Last Conformist]

What did your chemistry text book say exactly?

That all elements can occur in all three of solid, liquid, and gas at appropriate temperature and pressure, except for carbon, that lacks the liquid phase. Judging from Perf's link, this is flat out wrong. Just goes to show you shouldn't trust textbooks to far, I suppose.

 

[nonconformist]

That all elements can occur in all three of solid, liquid, and gas at appropriate temperature and pressure, except for carbon, that lacks the liquid phase. Judging from Perf's link, this is flat out wrong. Just goes to show you shouldn't trust textbooks to far, I suppose.

I guess we're using outdated textbooks.....

 

[ainwood]

sand,

Solid.

ketchup,

Its fluid (liquid) - called a 'bingham' fluid because it needs a minimum sheer stress to make it flow.

 

[SomethingWitty]

That all elements can occur in all three of solid, liquid, and gas at appropriate temperature and pressure, except for carbon, that lacks the liquid phase. Judging from Perf's link, this is flat out wrong. Just goes to show you shouldn't trust textbooks to far, I suppose.

Are you sure that's what it says? What's the exact quote?

 

[Masquerouge]

Solid.
Its fluid (liquid) - called a 'bingham' fluid because it needs a minimum sheer stress to make it flow.

Sand is a solid.
(Shaving) Foam is a liquid.
Paste is a liquid.
Magma is a liquid.

But how do you know ? What definition of solid,liquid and gas are you using ? That's what I'm looking for : a definition of solid, liquid and gas that I can apply to what I see in order to determine what it is.

Because if sand is a solid, it sure as heck doesn't behave as one.

 

[nonconformist]

Shaving foam is an emulsion.

Sand is a crystalline structure that's very small-each grain of sand is a solid, but many of them seem to flow.

Take billiard balls for example. They're quite solid. Now take thousands; you're able to pour them into a swimming pool, but they're still solid.

 

[Masquerouge]

That's actually a myth. The glass is thicker at the bottom due to old glassmaking methods, not because it's actually flowing.

Eh. At least I learned that. Thanks Now I can go to dinners and be a wise-ass

 

[Perfection]

But how do you know ? What definition of solid,liquid and gas are you using ? That's what I'm looking for : a definition of solid, liquid and gas that I can apply to what I see in order to determine what it is.

Because if sand is a solid, it sure as heck doesn't behave as one.

Wikipedia does a faily good job fleshing out the requirements.

 

[Masquerouge]

Wikipedia does a faily good job fleshing out the requirements.

Yep. It does. But I'm still worried about ketchup and sand

Can you freeze ketchup, btw ?

 

[The Last Conformist]

Because if sand is a solid, it sure as heck doesn't behave as one.

Sand is just very small rocks.

 

[Masquerouge]

Sand is just very small rocks.

How small can a rock be before it becomes a molecule ? In that case, SiO2 IIRC.

And glass is basically vitrified sand, and it's a solid. So you can get a solid from sand, yet sand itself is... nothing ?