# solubility of gases

#### inaccensa

10+ Year Member
7+ Year Member
The solubility of gases increases with increasing pressure. According to henry's law there are both proportional to one another C =kP.

However, EK states that the solubility of gases decreases with temp. I find this confusing, since Vapor pressure increases with temp,For liquids more molecules have sufficient energy to escape the liquid phase. Anyone correlate this with gases

#### rocuronium

10+ Year Member
Henry's law states that the amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas when in equilibrium with the liquid. One important caveat is the requirement for constant temperature.

For example, when a can of Coke is opened, the partial pressure above the liquid is reduced. This results in a lower solubility, causing a release of carbon dioxide (i.e. bubbles). Conversely, if you were to re-pressurize that can with carbon dioxide, more gas would dissolve in the liquid.

With regard to temperature, it is true that higher temperatures lead to lower gas solubility in liquid. You are correct with regard to vapour pressures; because more molecules have the energy to leave the liquid, more will do so. The result of this is less gas in solution. This fact is somewhat counter-intuitive when compared with solids, as the solubility of a solid in liquid increases with temperature.

Any carbonated beverage can be used as an example of this. If you leave some out in a cup, as it warms up the carbon dioxide will go out of solution (due to the decreased solubility), and the pop will go flat.

I hope this helps!

OP

#### inaccensa

10+ Year Member
7+ Year Member
Henry's law states that the amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas when in equilibrium with the liquid. One important caveat is the requirement for constant temperature.

For example, when a can of Coke is opened, the partial pressure above the liquid is reduced. This results in a lower solubility, causing a release of carbon dioxide (i.e. bubbles). Conversely, if you were to re-pressurize that can with carbon dioxide, more gas would dissolve in the liquid.

With regard to temperature, it is true that higher temperatures lead to lower gas solubility in liquid. You are correct with regard to vapour pressures; because more molecules have the energy to leave the liquid, more will do so. The result of this is less gas in solution. This fact is somewhat counter-intuitive when compared with solids, as the solubility of a solid in liquid increases with temperature.

Any carbonated beverage can be used as an example of this. If you leave some out in a cup, as it warms up the carbon dioxide will go out of solution (due to the decreased solubility), and the pop will go flat.

I hope this helps!

But why doesn't temp change work for gases?

#### rocuronium

10+ Year Member
But why doesn't temp change work for gases?
I'm not quite sure what you are asking.

#### sv3

10+ Year Member
Henry's law states that the amount of gas dissolved in a liquid is directly proportional to the partial pressure of that gas when in equilibrium with the liquid. One important caveat is the requirement for constant temperature.

For example, when a can of Coke is opened, the partial pressure above the liquid is reduced. This results in a lower solubility, causing a release of carbon dioxide (i.e. bubbles). Conversely, if you were to re-pressurize that can with carbon dioxide, more gas would dissolve in the liquid.

With regard to temperature, it is true that higher temperatures lead to lower gas solubility in liquid. You are correct with regard to vapour pressures; because more molecules have the energy to leave the liquid, more will do so. The result of this is less gas in solution. This fact is somewhat counter-intuitive when compared with solids, as the solubility of a solid in liquid increases with temperature.

Any carbonated beverage can be used as an example of this. If you leave some out in a cup, as it warms up the carbon dioxide will go out of solution (due to the decreased solubility), and the pop will go flat.

I hope this helps!
Now can you tell me how I could get you to take my MCAT for me and not get caught? Let's see you explain that!

#### rocuronium

10+ Year Member
Now can you tell me how I could get you to take my MCAT for me and not get caught? Let's see you explain that!
I'm afraid I have no solution to your problem. As tempting as it sounds, I don't think that I'll be writing that test again.

When I study I try to link the concepts and laws to real life examples. I find it much easier to remember things that way. For things like the gas laws it works very well.