[arisun2016]

Dear all,

Recently, I made a liquid with a solid organic powder and a organic gas. (Sorry I cannot give the details of materials now).
The solid powder (1 mol) can absorb the gas (2 mol) by forming hydrogen bonds between molecules and then become liquid.
If I call the liquid is solution, what is the solvent? It seems we cannot call the gas is solvent.

Could you please tell me the proper way to call the liquid?

Thank you in advance!

arisun2016

[Arkcon]

Here is a resource for you: https://en.wikipedia.org/wiki/Solution

You can find this description in any high school text book.  Its common for a solution to take the phase of the solvent, but not required.  At any rate, a solution can be a solid in a gas, or a solid in a solid.

Dear all,

Recently, I made a liquid with a solid organic powder and a organic gas. (Sorry I cannot give the details of materials now).

Urm.  OK.

The solid powder (1 mol) can absorb the gas (2 mol) by forming hydrogen bonds between molecules and then become liquid.

Sure. 

If I call the liquid is solution, what is the solvent? It seems we cannot call the gas is solvent.

Could you please tell me the proper way to call the liquid?

Thank you in advance!

arisun2016

[arisun2016]

Dear Arkcon,

Thank you for your reply!
I have learned the wiki webpage.
It defined the cases of gas in gas solvent, gas or liquid or solid in liquid solvent, and those in solid solvent.
But there's no case of solid in gas solvent.
Could you explain more?

With many thanks.
Arisun

[Dan]

Could you call it a liquid adduct/complex? Like BF₃·Et₂O or Et₃N·3HF

[Arkcon]

First of all, the wikipedia page says that the situation can't occur, or at least, we don't call it a solution.

Meh.  smoke, or dust suspended in air is a colloid, or a sol, not a solution, because its not homogeneous enough.  But the Wikipedia page mentions a solution may not be homogeneous.  Just words.

OK.  A hypothetical:  calcium chloride is a solid.  Water vapor in the air is a gas.  Calcium chloride is deliquescent, its so hygroscopic it draws moisture from the air, dissolving itself into a liquid solution.  But if I add calcium chloride to liquid water, I get the same solution.  So its not all that impressive how it got there.

[arisun2016]

Could you call it a liquid adduct/complex? Like BF₃·Et₂O or Et₃N·3HF

Dear Dan,

Thank you for your suggestion.
That sounds good.

arisun2016

[arisun2016]

Dear Arkcon,

Thank you for your reply.
I understood your insistence on the opinion of gas solvent and accept it.

arisun2016

[arisun2016]

Dear Arkcon,

Today I found the solid can not absorb more gas at room temperature and one atmospheric presure when the mol ratio between them is increased to 1:4.
This is very different with normal solvent which has unlimited ratio to solute in same condition.
In this case, may we conclude that the gas is absolutely not a solvent at room temperature and one atmospheric presure?

Thanks,
arisun2016

[arisun2016]

First of all, the wikipedia page says that the situation can't occur, or at least, we don't call it a solution.

Meh.  smoke, or dust suspended in air is a colloid, or a sol, not a solution, because its not homogeneous enough.  But the Wikipedia page mentions a solution may not be homogeneous.  Just words.

OK.  A hypothetical:  calcium chloride is a solid.  Water vapor in the air is a gas.  Calcium chloride is deliquescent, its so hygroscopic it draws moisture from the air, dissolving itself into a liquid solution.  But if I add calcium chloride to liquid water, I get the same solution.  So its not all that impressive how it got there.

Dear Arkcon,

Today I found the solid can not absorb more gas at room temperature and one atmospheric presure when the mol ratio between them is increased to 1:4.
This is very different with normal solvent which has unlimited ratio to solute in same condition.
In this case, may we conclude that the gas is absolutely not a solvent at room temperature and one atmospheric presure?

Thanks,
arisun2016

[Arkcon]

Today I found the solid can not absorb more gas at room temperature and one atmospheric presure when the mol ratio between them is increased to 1:4.

OK.  That's clear and easy to understand.

This is very different with normal solvent which has unlimited ratio to solute in same condition.

And this is not true.  A solution of a solid in water eventually saturates.  Think about it critically:  can you dissolve as much sodium chloride in water as you want?

In this case, may we conclude that the gas is absolutely not a solvent at room temperature and one atmospheric presure?

No.  But why would we?  We've established above, that the solid is the solvent for the gas.  Correct?

[arisun2016]

Dear Arkcon,

Please see my reply again.
The molar ratio between the solid and the adsorbed gas is in the range of 1:0 to 1:4 where the amount of adsorbed gas has a upper limit.
However, in normal solution, the molar ratio between solute and solvent is saturated ratio to 1:∞ where the amount of solvent has no upper limit.
For NaCl, the saturated ratio is about 0.11 (35.9g NaCl in 100g wather at room temperature).

Do you think the gas is a kind of solvent in my case?

[Borek]

The molar ratio between the solid and the adsorbed gas is in the range of 1:0 to 1:4 where the amount of adsorbed gas has a upper limit.

Where do theses limits for composition come from?

The situation you described sounds like a deliquescence - for example calcium chloride if left in the open will typically absorb enough water to become a solution. However, once it becomes dissolved there is no upper limit to the amount of water that can be used to dilute the solution (which doesn't mean it will absorb water on its own).

[arisun2016]

The molar ratio between the solid and the adsorbed gas is in the range of 1:0 to 1:4 where the amount of adsorbed gas has a upper limit.

Where do theses limits for composition come from?

The situation you described sounds like a deliquescence - for example calcium chloride if left in the open will typically absorb enough water to become a solution. However, once it becomes dissolved there is no upper limit to the amount of water that can be used to dilute the solution (which doesn't mean it will absorb water on its own).

Dear Borek,

Thank you for your discussion.

Sorry for all that I forget to mention that the boiling point of the used gas is under 0 °C.
I think when I say something gas then that's mean it is in gas phase under room temperature and one atmospheric presure.
Yes, under room temperature and one atmospheric presure, it is in gas phase, and so it is not like water to dissolve the solid.

Thanks,
arisun2016

[Borek]

Yes, under room temperature and one atmospheric presure, it is in gas phase, and so it is not like water to dissolve the solid.

Deliquescence doesn't require water to be in a liquid phase, quite the opposite - it starts with water being gaseous.

I am not aware of a specific name describing your mixture (other than solution of the solid in the other substance).

[arisun2016]

Yes, under room temperature and one atmospheric presure, it is in gas phase, and so it is not like water to dissolve the solid.

Deliquescence doesn't require water to be in a liquid phase, quite the opposite - it starts with water being gaseous.

I am not aware of a specific name describing your mixture (other than solution of the solid in the other substance).

Dear Borek and others,

Let's imagine to add my solid into my gas (100 mol) in comparison with the normal process of dissolution like NaCl in water (100 mol).

A, I added 1 mol solid into 100 mol gas and got 1 mol liquid/mixture (solid:3gas molecules) and 97 mol gas. The phases of liquid and gas are separated naturally.
B, I added 1 mol NaCl into 100 mol water and got 1 mol% solution with NaCl uniformly distributed. Here liquid phase only.

The difference is obvious.

The question is that the gas is a kind of solvent or not.

Please tell me frankly.

Many thanks,
arisun2016