Acids, Bases, and Acids, Bases, and SolutionsSolutions

Chapter 7Chapter 7

Mrs. JenkinsMrs. Jenkins

What is a solution, solvent, What is a solution, solvent, and solute?and solute?

What is a solution?What is a solution?

A well-mixed mixture that contains a solvent A well-mixed mixture that contains a solvent and at least one soluteand at least one solute

Ex. Tap Water, Ocean Water, Soda WaterEx. Tap Water, Ocean Water, Soda Water

What is a solvent?What is a solvent?

The part of the solution present in the largest The part of the solution present in the largest amountamount

It dissolves the other substancesIt dissolves the other substances

Ex. Liquid in Tap WaterEx. Liquid in Tap Water

What is a solute?What is a solute?

The substance that is present in a solution is a The substance that is present in a solution is a smaller amount and is dissolved by the solventsmaller amount and is dissolved by the solvent

Colloids and Colloids and SuspensionsSuspensions

Colloids and Suspensions are mixtures Colloids and Suspensions are mixtures that have different properties than that have different properties than solutions.solutions.

What is a colloid?

Is a mixture containing small, undissolved small, undissolved particles that do not settle outparticles that do not settle out

A colloid contains larger particles than a A colloid contains larger particles than a solutionsolution

Ex. Fog, milk, mayonnaise, shaving creamEx. Fog, milk, mayonnaise, shaving cream

Colloids and Colloids and SuspensionsSuspensions

What is a suspension?What is a suspension?

Is a mixture containing small, small, undissolved particles that do not settle undissolved particles that do not settle outout

Have you ever noticed that pepper and Have you ever noticed that pepper and water do not mix completely? This is an water do not mix completely? This is an example of a “suspension.”example of a “suspension.”

A suspension is a mixture in which A suspension is a mixture in which particles can be seen and easily particles can be seen and easily separated by settling or filtration.separated by settling or filtration.

It contains particles that are even larger It contains particles that are even larger than solutions or colloids.than solutions or colloids.

Solutions and Solutions and ConductivityConductivity

How would you know if a solution How would you know if a solution can conduct electricity or not?can conduct electricity or not?

A solution of ionic compounds in A solution of ionic compounds in water conducts electricity, but a water conducts electricity, but a water solution of molecular water solution of molecular compounds may not.compounds may not.

If no ions are present ( as is a If no ions are present ( as is a sugar solution) electricity will sugar solution) electricity will not flow.not flow.

Effects of Solutes Effects of Solutes on Solventson Solvents

The freezing point of water is 0 degrees and The freezing point of water is 0 degrees and the boiling point is 100 degrees. When you the boiling point is 100 degrees. When you add a solute to the solution it will LOWER add a solute to the solution it will LOWER the freezing point and RAISE the boiling the freezing point and RAISE the boiling point of a solvent.point of a solvent.

When you have water freezing at 0 degrees When you have water freezing at 0 degrees C to form crystals of solid ice, it is a lot C to form crystals of solid ice, it is a lot harder to freeze at 0 degrees if you add salt harder to freeze at 0 degrees if you add salt to that water. You LOWER the freezing point to that water. You LOWER the freezing point below 0 degrees for the solution to freeze.below 0 degrees for the solution to freeze.

Effects of Solutes Effects of Solutes on Solventson Solvents

Solutes raise the boiling point of a solventSolutes raise the boiling point of a solvent

In a liquid, molecules are moving close to In a liquid, molecules are moving close to each other, but in a gas they are far apart each other, but in a gas they are far apart and are moving more rapidly.and are moving more rapidly.

As the temperature of a liquid rises, the As the temperature of a liquid rises, the molecules gain energy and escape into molecules gain energy and escape into the air.the air.

Question: Does salt water have a lower or Question: Does salt water have a lower or high freezing point than pure water? high freezing point than pure water?

Concentration and Solubility

What is a concentrated solution?

One that as a lot of solute dissolved in the same amount of solvent

Ex. Syrup

What is a dilute solution?

A Mixture that has only a little solute dissolved in a certain amount of solvent

Ex. Sap of a Maple Tree

Changing and Measuring

ConcentrationHow do you change the amount of concentration?

By adding more solute or by adding or removing solvent

Ex. When you make juice which is a concentrated solution, you add water to make it more diluted

To measure the amount of concentrated, you compare the amount of solute to the amount of solvent

SolubilityWhat is solubility?

Solubility is the amount of solute that can dissolve in a solvent at a given temperature.

When it is a saturated solution, that means you have added so much solute that no more will dissolve.

When it is supersaturated, you have more solute than you do solvent to dissolve.

When it is unsaturated, is when you can still dissolve the solute.

Factors that affect Solubility

What are the three factors that affect the solubility of a substance?

Pressure, type of solvent, and temperature

What happens when you increase the pressure of a substance?

The higher the pressure, the more dissolved

Factors that affect Solubility

How is the solubility affected by the type of solvent?

“Like dissolves like”….so ionic and polar molecules dissolve well in polar solvents.

What happens when you increase the temperature?

For most solids, solubility increase with an increase in temperature.

Gases become less soluble when you increase the temperature.

Why does warm soda taste flat?

It contains less gas.