1. Classification of Matter
Pure Substances
Elements
Compounds
Mixtures
Heterogeneous Mixtures
Homogeneous Mixtures
Classification of Matter

2. Pure Substance Matter with constant composition
Matter Anything with mass and volume.
Pure Substance Matter with constant composition
Mixture Matter with variable composition
Element Substance made up of only one type of atom
Compound Two or more elements that are chemically combined
Heterogeneous Mixture Mixtures that do not appear the same throughout
Homogeneous Mixtures Mixtures that appear to be the same throughout
Examples - gold, silver, carbon, oxygen and hydrogen
Examples - water, carbon dioxide, sodium bicarbonate, carbon monoxide
Examples - sand, soil, chicken soup, pizza, tossed salad, chocolate chip cookies.
Examples - salt water, pure air, metal alloys, seltzer water.

3. Pure Substances Compounds Elements Purest form of matter.
Made up of only one type of atom.
Cannot be broken down by ordinary chemical means.
Substance made up of atoms of more than one element, chemically combined.
Can be decomposed, or broke down by chemical reactions.

4. What is the purest form of matter?
Elements
Compounds
Mixtures
Solutions

5. More about compounds
Properties of a compound are different than the properties of the elements that make them up.
Sodium(Na)
soft, silvery white
Very reactive in water
Chlorine(Cl)
Pale green poisonous gas
Table Salt(NaCl)
You put it on your french fries!

6. Properties of Mixtures
Each substance has its own unique properties
Substances may change physical appearance.
Substances can be present in any amount.
Mixtures can be separated by ordinary means.

7. Heterogeneous vs. Homogeneous Mixtures
Heterogeneous Mixture
Homogeneous Mixture
Do not appear the same throughout
Components will separate or settle out
Appears to be the same throughout
Components will not separate

9. Suspensions Type of mixture that will “settle” out!!
Will not scatter light(Can’t see a beam of light through it!!)!.

10. Colloids Appear homogeneous to the naked eye.
Will scatter light(Can see a beam of light through it).

11. Solution
Type of homogeneous mixture in which one substance completely dissolves in another.
“Best mixed mixture!!”
2 parts:
Solute—substance that dissolves
Solvent—substance that the solute dissolves in

12. Soluble vs. Insoluble Soluble Insoluble
A substance is said to be soluble in a substance, when it will dissolve in that substance.
A substance is said to be insoluble in a substance, when it will not dissolve in that substance.
Some substances are soluble in one solvent, but insoluble in another solvent.

13. Solubility
Amount of solute that can be completely dissolved in a given amount of solvent.
Solubility Curve—Curve showing how temperature affects the solubility of a substance.

15. Discuss:
Solids vs. Gases
….in 100 g of H2O
Axes

16. How many grams of KNO3 will dissolve in 100 g of water at 60o C?

17. At what temperature will approximately 95 g of NaNO3 dissolve in 100 g of water?
30 oC

18. At what temperature will the same amount of KNO3 and NaNO3 dissolve in 100 g of water?
~ 68 oC

19. At what temperature will exactly 51 g of Na2SO4 dissolve in 100 g of water?
20 oC
30 oC
40 oC
50 oC

20. How much HCl will dissolve in 100 g of water at 75 oC?

21. At what temperature will the exact same amount of HCl and KCl dissolve in 100 g of water?
50 oC
65 oC
75 oC
90 oC

22. Levels of Saturation
Unsaturated solution—solution “could” dissolve more solute.
Saturated solution—Solution has dissolved all the solute possible.
Supersaturated solution—Solution has dissolved all solute possible, but more solute is added anyway.

23. Can’t but about 50 g dissolve at 80 oC.
Which term would describe a solution of 90 g of KCl dissolved in 100 g of water at 80 oC?
Unsaturated
Saturated
Supersaturated
Can’t but about 50 g dissolve at 80 oC.

24. Suppose 90 g of KI are placed in 100 g of water at 10 oC
Suppose 90 g of KI are placed in 100 g of water at 10 oC. What type of solution would you have?
Unsaturated
Saturated
Supersaturated
Could dissolve about 135 g.

25. Suppose you place 90 g of NH4Cl in 100 g of water at 70 oC
Suppose you place 90 g of NH4Cl in 100 g of water at 70 oC. What type of solution would you have?
Unsaturated
Saturated
Supersaturated