1. Pure substances contain only one kind of matter.
NaCl Cr
Element
Compound

2. Physical Property is a quality or a condition of a substance that can be observed or measured without changing the substance’s composition.
Color
Size
Hardness
Density
Shape
Odor
Melting Point
Boiling Point

3. Change in matter without changing the chemical composition.
Physical Change
Change in matter without changing the chemical composition.
Examples:
Boiling
Cutting
Melting
Splitting
Cracking
Condensing
Freezing
Bending
Breaking
Grinding
Crushing

4. - Chemical Change – one or more substances changing into a new substance.
Signs of a chemical change:
1. Bubbling
2. Change in Temp
3. Color Change
4. Change in Smell

6. Write the indicators of a chemical change for each of the following:
A firecracker explodes
A piece of wood burns
An antacid tablet is dropped in water

7. 2.2 Mixture Heterogeneous a physical blend of two or more substances.
not uniform in composition
Examples:
Muddy Water
Chocolate-Chip Cookie
Salad

8. Solutions are homogeneous mixtures. They consist of one phase.
completely uniform in composition
Examples:
Milk
Salt water
Solutions are homogeneous mixtures. They consist of one phase.

9. any part of a system with uniform composition and properties.
Phase
any part of a system with uniform composition and properties.
Heterogeneous mixtures
consist of 2 or more phases
Homogeneous mixtures
consist of one phase

10. 2.3 Element Examples: Al C Hg
The simplest form of matter that can exist under normal laboratory conditions.
Examples: Al C Hg

11. Compound Examples: AlCl3 NaCl H2CO3 CH3OH
A substance that can be separated into simpler substances only by chemical means.
Examples:
AlCl3
NaCl
H2CO3
CH3OH

13. Classify the following as an element, compound or mixture:
C12H22O11
Table sugar
Water
Iron
Vegetable Soup
Salt water O2
CaCO3
Air
Compound
Element
Mixture

14. mass of reactants = mass of products
2.4
Law of Conservation of Mass
Mass is neither created nor destroyed in chemical reactions.
mass of reactants = mass of products
In a chemical reaction, the numbers and kinds of atoms present in the products are the same as those present in the reactants.