1. Unit 1B: Introduction to Chemistry
Ms. Wallace
General Chemistry

2. I. Important Terms Chemistry: Matter:
The study of matter and its changes
Any object that has a mass and volume (pretty much anything)

3. I. Important Terms Atom: -
Particle Diagram:
Smallest particle of an element that retains the properties of that element
Can not be broken down by a chemical reaction
2 different types of elements

4. I. Important Terms Compound: -
Particle Diagram:
Two ore more DIFFERENT ELEMENTS BONDED together
Can be broken down by a chemical reaction
1 type of compound

5. II. Phases of Matter The phases that matter is in depends on:
1. The space between atoms or molecules
2. The strength of the intermolecular force (IMF) between atoms

6. Takes shape of con-tainer definite Med-ium Vibrate and rotate
Phase
Shape
Volume
IMF
Movement
Solid (s)
Liquid (l)
Gas (g)
definite
definite
strong
vibrate
Takes shape of con-tainer
definite
Med-ium
Vibrate and rotate
Takes shape of con- tainer
Takes shape of con- tainer
weak
Vibrate and rotate

7. III. Classification of Matter
Element (Column A):
Compound (Column B):
Mixture (Column C):
Substance that cannot be changed into a simpler substance under normal conditions
Substance consisting of 2 or more different chemical elements that can be separated by chemical reactions (heat, electricity)
A physical blend of 2 or more substances that are NOT chemically combined (air, soup, tap water)

8. Aqueous Solution (aq):
a mixture of water and some other substance that can dissolve in water (salt water)
Element
Compound
Mixture

9. How Elements, Compounds, and Mixtures can be illustrated
N2 (g)
CO2 (g)
Air (N2, O2, H20, CO2(g)

10. Cool Animation

11. IV. Physical vs. Chemical Properties
Properties of an element or compound that can be observed or measured WITHOUT a chemical reaction
Ability of an element or substance to undergo a chemical reaction (bond breaking) and form a NEW substance

12. IV. Physical vs. Chemical Properties
Color, texture, odor, density, melting/freezing temps, solubility, volume, mass
VIDEO EXAMPLE
Reactivity, pH (acidity), ability to rust, decompose, ferment, combust
VIDEO EXAMPLE

13. IV. Physical vs. Chemical Properties

14. V. Physical vs. Chemical Changes
A change that does NOT produce a new substance, it just changes the position of the particles
Changing a substance into a NEW substance (bonds are broken and then new ones formed)
A color change may occur and a NEW s, l, or g is formed
A change that does NOT affect a substance’s chemical position

15. V. Physical vs. Chemical Changes
Any phase change (freezing, melting…), dissolving, mixing, cutting
Burning, rusting, fermentation, cooking/baking

16. V. Physical vs. Chemical Changes
liquid water freezes to ice
salt dissolves in water
liquid nitrogen in plastic bottle bursts open
rusting on a pan
potassium reacting with water to form potassium hydroxide and hydrogen gas
2K (s) + 2H2O (l) -> 2KOH (aq) + H2 (g)

17. IV. Physical vs. Chemical Properties

18. A chemical reaction ALWAYS results in a new substance
Chemical Reaction Equation:
4 H
+2 O
6 Total
4 H
+2 O
6 Total =
Reactants
Products
2 H2 (g) + O2 (g)  2 H2O (l)
Coefficient
# of atoms
A chemical reaction ALWAYS results in a new substance

19. Mass cannot be created or destroyed in a chemical reaction
Conservation of Mass:
Mass cannot be created or destroyed in a chemical reaction
The total mass of reactants equals the total mass of the products
Example (video clip)
Silver nitrate (AgNO3) and sodium chloride (NaCl) solutions before and after mixing

20. Examples: 50 g + Sodium+ 76 g 126 g Sodium Chloride Chlorine 
1) If 50.0 grams of sodium reacts with chlorine to form 126 grams of sodium chloride. How many grams of chlorine reacted?
2) If g of water is separated into hydrogen and oxygen gas, and the hydrogen gas has a mass of 20.0 g. What is the mass of the oxygen gas produced?
50 g +
Sodium+
76 g
126 g
Sodium Chloride
Chlorine 
178.8 g 
H2O 
20 g +
158.8 g
H2 + O2

21. Definite Composition (Homogeneous)
VI. Classification of Matter Chart
Matter
Substance
Definite Composition (Homogeneous)
Physically
Separable
Mixture of Substances

22. Nonuniform; distinct phases
VI. Classification of Matter Chart
Mixture of Substances
Homogeneous
Uniform throughout (air, tap water, gold alloy, salt water, Kool-Aid)
AKA – SOLUTIONS
Heterogeneous
Nonuniform; distinct phases
(soup, concrete)

23. Water (H2O), Carbon Dioxide (CO2)
VI. Classification of Matter Chart
Substance
Element
Iron, Sulfur, Oxygen
Compound
Water (H2O), Carbon Dioxide (CO2)
Chemically
Separable