Mixtures and Solutions 2

Diluted Solutions Vs Concentrated Solutions

• A dilute solution has a small proportion of solute when compared with a concentrated solution.

Experience Chemistry | Lesson 5.4.2

​Vocabulary

​

• solute = what is being dissolved (Ex: Lemonade powder)

• ​solvent = what is doing the dissolving (Ex: Water)

• ​solution = the result (Ex: Lemonade)

• ​soluble = CAN dissolve in water

• ​insoluble = CANNOT dissolve in water

Match

Identify a solute, the solvent, and the solution in a carbonated drink (like soda).​

• Carbon Dioxide (dissolved in the drink)

• Water

• The Carbonated Drink

Solute

Solvent

Solution

• Solute

• Solvent

• Solution

​How to determine solubility?

​Solubility

Solubility is determined based on a substance ability to dissolve. A substance such as sand is considered to be insoluble (-unable to dissolve) because when sand and water is mixed, the solute sand, settles at the bottom. Sugar on the other hand, when mixed in water is considered to be soluble (-capable of being dissolved) because when sugar is mixed in water it dissolves evenly amongst the solvent.​

Agitation - Recap

Stirring or agitating a solution increases the amount of solute/solvent interactions mechanically.

Increasing solute/solvent interactions increases rate of dissolution.

This is why you stir the Kool-aid when you add it to the water.

Salt water concentration

Concentration in solutions

Concentration

Concentration refers to the amount of solute dissolved in a volume of solvent.

The more solute that is dissolved in a solvent, the more concentrated the solution is.

A solution that is not very concentrated is a dilute solution.

Multiple Choice

If you want to make a solution more concentrated, you should add more

• solute

• solvent

• love

Multiple Choice

Which of the following solutions is the most diluted?

• A solution of 5 grams of salt with a volume of 100 mL.

• A solution of 10 grams of salt with a volume of 1000 mL.

• A solution of 20 grams of salt with a volume of 1000 mL.

• A solution of 50 grams of salt with a volume of 1000 mL.

Saturated Solution

• A saturated solution is a solution in which no more solute can dissolve.

• At the saturation point, all of the solute is dissolved, but adding more solute will leave some undissolved.

Multiple Choice

A ________ is a solution in which no more solute can dissolve.

• saturated solution

• unsaturated solution

• supersaturated solution

Supersaturated Solutions

• A supersaturated solution is a solution that contains more solute than a saturated solution.

• Usually, this results in undissolved material that tends to crystallize.

Solubility

The amount of solute that will dissolve in a solvent is its solubility. Solubility depends on the solvent.

Multiple Choice

In which way is solubility different than concentration?

• Unlike concentration, solubility does not depend on the amount of solvent.

• Solubility can change based on temperature and pressure, but concentration can only change due to the total volume of solution.

• Solubility is a measurement of how much solute can possibly dissolve, but concentration is a measurement of how much solute is dissolved.

• Unlike concentration, solubility depends on the amount of solute dissolved in the total solution.

Multiple Choice

Solubility is the ability of a solute to dissolve into a solution. Which of the following statements is true about solubility?

• More solute can dissolve in a solution if its solubility is high.

• More solute can dissolve in a solution if its solubility is low.

• Less solute can dissolve in a solution if its solubility is high.

• The amount of solute that can dissolve depends on the solvent, not solubility.

Factors affecting rate of solubility

• Temperature

• Pressure

• Rate of stirring/mixing

• Size of solute particles

Separating Mixtures-Physical Means

• There are many ways to separate mixtures into their components, and what you do depends on your ultimate goal

  • Physical methods

    • Decanting

    • Centrifuging

    • Filtration

    • Evaporation​

Separating Mixtures- other methods

• Chromatography separates components of a mixture based on how quickly different molecules dissolved in a mobile phase solvent move along a solid plane

• Distillation separates mixtures based on evaporation point

Multiple Choice

What does it mean to be "Soluble" ?

• Capable of being a solid.

• To have soul.

• Capable of being dissolved.

• To sink.