1. Chemistry
Solutions Unit

2. A solution is a homogenous mixture
What is a solution?
A solution is a homogenous mixture

3. In a homogenous mixture,
You cannot identify what the mixture is made up of.
It looks the same throughout

4. What are the two main parts of a solution?
1. The Solute- the dissolved substance (usually in a smaller amount)
Ex. Sugar, salt
2. The Solvent- the dissolver (usually in a larger amount)
Ex. Water

5. What is the Universal solvent?
Water
Because of the unique polarity of water molecules, water is able to dissolve many different solutes.

6. How are solutions formed?
Through a process called Solvation also known as dissolving. The nature of the solute and solvent, determine whether a substance will dissolve.

7. What affects the rate of solvation?
Heating
Stirring
Surface Area

8. How does heating affect dissolving?
At higher temperature, the molecules of the solvent move around faster and contact the solute more often. Speeds up dissolving.

9. How does stirring affect dissolving?
Stirring moves fresh solvent into contact with the solute.

10. How does surface area affect dissolving?
Smaller pieces increase the amount of surface area of the solute.
Ex. Think of how fast a breath mint dissolves when you chew it

11. Solids tend to dissolve best when:
Heated
Stirred
Ground into smaller particles
Gases tend to dissolve best when:
The solution is cold
Pressure is high

12. What is Solubility?
The maximum amount of substance that will be dissolved at a specific temperature Units are: g of solute 100 g of H2O

13. What are the types of solutions?
Unsaturated
Saturated
Supersaturated

14. What is an unsaturated solution?
A solution where more solutes can be added and will completely dissolve.

15. What is an Saturated solution?
A solution that contains the maximum amount of solutes dissolved

16. What is a Supersaturated solution?
A solution that contains more solutes than it can hold.

17. How do you know that a solution is Supersaturated?
The solutes will settle to the bottom of the container and will eventually begin to crystallize.

18. How do we know what type of solution?
We use Solubility Curves!

19. Warm Up
What are the three types of solutions? Define each

20. Solids dissolved in liquids
As the temperature goes up, the solubility usually goes up
This is shown by upward curved lines.

21. Gases dissolved in liquids
The effect is the opposite of solids in liquids, as the temperature goes up, gas solubility goes down
This is shown by the downward curving graphs.

22. Warm Up 04/14
Identify and define the three types of solutions. Must be a minimum of 3 sentences long.

23. Warm Up 04/15
Complete this sentence: I can speed up the rate of dissolving by……

24. This the measure of how much solute is dissolved in a solvent.
What is concentration?
This the measure of how much solute is dissolved in a solvent.

25. How do you calculate concentration for solutions?
We use Molarity! Represented by a big M

26. What is the formula?

27. Let’s practice
0.5 moles of NaCl is dissolved to make 0.05 liters. Calculate the molarity.

28. Let’s practice
How many moles of Na2CO3 are there in 10.0 L of 2.0M solution?

29. What is it called when a substance dissolves?
Soluble
Ex. Salt is soluble in water

30. What is it called when a substance does not dissolve?
Insoluble Ex. Chalk in insoluble in water

31. What is it called when something dissolves in water?
An aqueous solution Abbreviated (aq)

32. What is it called when a solid forms in a solution?
A precipitate

33. How do some solutes dissolve in a solvent and others do not?
It depends on the polarity of both the solute and the solvent.

34. The “Like dissolves like” rule
How does this work?
The “Like dissolves like” rule

35. A polar substance will dissolve another polar substance
What does this mean?
A polar substance will dissolve another polar substance

36. Example
Ex. Salt will dissolve in water

37. Water is polar Other polar substances will dissolve in water

38. Why is water polar?
Because of its bent shape and the negative and positive ends of the molecule

39. A non-polar substance will dissolve another non- polar substance
Example
A non-polar substance will dissolve another non- polar substance
Ex. Vegetable oil in Acetone

40. What happens if you mix a polar and a non-polar substance?
They DO NOT MIX!!!!

41. Use the Solubility Chart to tell if a substance will dissolve in water!

42. How do you know if a reaction will happen?
A solid (precipitate) product MUST be produced for a reaction to occur. Ex. (aq) + (aq)  (aq) + (s) A reaction occurs!!!

43. What is produced when two (aq) products are formed?
Ex. (aq) + (aq)  (aq) + (aq) A mixture forms!!

44. What is a water solution that conducts electricity called?
An electrolyte

45. What is a metal solution called?
An alloy This solution contains two or more metals mixed.

46. Examples of Alloys
Brass
Bronze
Sterling silver

47. What are heterogenous mixtures called?
Suspensions
Particles settle
They can be easily separated by filtration

48. Examples
Sand and water

49. What are colloids?
Uniform mixtures that do not settle but instead are dispersed throughout the solvent

50. Examples of colloids
Milk Lotion Fog

51. What is Tyndall effect?
This is the scattering of light of colloidal particles. Solutions CANNOT scatter light.

52. What is the Tyndall effect used for?
It is used to distinguish between solutions and colloids