Solubility Sometimes things are not capable of mixing, and will not dissolve within a solvent. This means that the two are Insoluble. This means that there is something about one of the two of them that doesn’t allow the other to hide within them.

Solubility What do you think keeps things from mixing together?

Solubility For most of our examples we have water as the solvent, so lets look at how it works as one. Water is a polar molecule. What does that mean?

Solubility It means that it is unbalanced in charge across the molecule, some areas are more negative than others, making the opposite areas positive.

Solubility Oxygen is more electronegative than Hydrogen, if you remember the trends along the periodic table. This means that it likes to take in electrons and hold on to negative charges more than Hydrogen does.

Solubility You can see this by looking at the diagrams below, the arrows point to the direction of electron attraction, this creates an increased density of electrons near the Oxygen.

Solubility This turns the water molecules into tiny little magnets that have the ability to attract and repel things.

Solubility Because water has a positive end that attracts negative ends of other molecules, and a negative end that attracts positive ends, we can dissolve things that have both of those aspects within them. Can you think of a compound that is made up of a positive and negative together? Salt! Na+Cl-!

Solubility

Solubility What is this molecule? Do you think by looking at it that it will be able to be dissolved in water? I’m sure you do it all of the time.

Solubility What is this molecule? Do you think by looking at it that it will be able to be dissolved in water? I’m sure you do it all of the time.

Solubility Solids do not dissolve instantly when placed in the water, they are usually crystals of many individual molecules clumped together. They need to be separated into their individual units before they can be solvated. That is why you can see the salt or the sugar that you pour into the water for a moment before you stir it in.

Solubility This doesn’t have to always be with a solid in a liquid. Liquids can dissolve each other too. When a liquid is capable of dissolving within another, they are said to be miscible. For example, acetic acid and water are miscible

Solubility Now that you know what makes something soluble, can you think of things that would make something insoluble in something else? Things like to dissolve within something that they are similar to. The rule is : Like Dissolves Like This means that polar solvents dissolve polar solutes The opposite is also true, non-polar solvents dissolve non- polar solutes

Non-Polar molecules in solution Example: Gasoline! This is a solution of many different hydrocarbons that are able to mix together because the are like each other in polarity, they have very little!

Non-Polar Molecules There is no attraction between the different molecules of gasoline, so how do they mix and spread out? It is because the different types of molecules are not attracted to themselves either, so they don’t care if they are beside one of themselves, or beside something different Eventually over time they evenly spread out due to ENTROPY

Solubility So lets go back to the oil and water example. Why do they not mix? Remember how like dissolves like. If water is polar, what does that make the oil?

Solubility Vegetable oil!

Origins of life began because of this! Do you know what this is?

Origins of life began because of this! Because of the molecule having a part of it that is HYDROPHOBIC and the opposite end being HYDROPHILIC this makes it act funny when in water.

SOLUTIONS: THE SOLUTION TO LIFE (LOL)

Solubility So if liquids that are capable of dissolving one another are known as miscible, what do you think oil and water are known as? IMMISCIBLE Can you think of some other liquids that are immiscible?

I feel pretty. I hope they get all of it… HALP! I’m covered in an oil spill! DAMN YOU BP!!! I hope they get all of it…

Things that change solubility. In order for something to become a solution, the solute and the solvent need to come in contact with each other. There are a few ways to increase the change of the molecules to come in contact: Agitation: Stirring or shaking a mixture will help increase the amount of collisions and helps to spread out the solute amongst the solvent.

Things that change solubility. Surface Area: The smaller the solute pieces, the more surface area is available for contact with the solvent, this is why granulated sugar dissolves faster than a sugar cube does. Temperature: Things will dissolve quicker if there is a higher temperature involved. Relate this back to particle theory, things are moving faster, therefore more collisions between the solute and solvent.

Things that change solubility. Stirring the mixture Increase the surface area Raise the temperature

Saturation This is a measure of how much solute is dissolved in a solvent. Saturated Solution: This is a solution that is carrying as much solute as it possibly can for the given temperature and pressure. Unsaturated Solution: This is when the solution is capable of holding more solute, so it has less solute than the saturated solution at the same temperature and pressure.

Saturation Supersaturated Solution: This is where the solution is holding more solute within it than the saturated solution of the same temperature and pressure.

How do you get a Supersaturated Solution? If a saturated solution is one that is holding the maximum, how can there even be a supersaturated solution? We can break the rules and force it to hold more by manipulating the temperatures or pressures. Lets find out how it works!!