1. Warm Up: 9/24 (Back of NB)
Use a periodic table and your knowledge of the element families to identify each element by name. 1. I am a member of the Carbon family with 14 electrons. 2. I am a member of the Alkaline Earth family and would have 6 energy levels. 3. I am a halide that is a liquid at room temperature. 4. I am a transition metal with 79 protons. 5. I am a member of the Alkali Metal family with 20 neutrons.

2. The answers are …
1. I am a member of the Carbon family with 14 electrons.
2. I am a member of the Alkaline Earth family and would have 6 energy levels.
3. I am a halide that is a liquid at room temperature.
4. I am a transition metal with 79 protons.
5. I am a member of the Alkali Metal family with 20 neutrons.
Silicon
Barium
Bromine
Gold
Potassium

3. Both physical and chemical properties are used to describe substances.

4. Review: What are physical properties?
List some examples of physical properties:
Color
Shape
Odor
Mass
Volume
Density
Melting point
Boiling point
Solubility
Malleability
Ductility
Conductivity

5. Chemical Properties
Characteristics of substances that give them the ability to undergo a change that results in a new substance.
Click here to watch a video

6. Examples of Chemical Properties:
Flammability – easily set on fire. (ash and smoke are the new substances formed)
Oxidation – reacting with oxygen (tarnish)
Rust – some metals react with water to form a new substance, rust.

7. Examples of Chemical Properties:
Radioactivity -
An atom’s nucleus, if unstable, will spontaneously decompose to form a new atom with a higher stability. (loss of protons)
The decomposition process is called radioactivity.

8. Properties Practice
Use your notes to determine if these are examples of physical (p) or chemical (c) characteristics.
_____ Sodium (Na) is a very reactive alkali metal.
_____ Oxygen (O) is a gas.
_____ Wood is flammable.
_____ A ruby is red.
_____ Copper (Cu) conducts electricity.
_____ Water (H2O) freezes at 0 degrees Celsius.
_____ Iron (Fe) reacts with water to form rust.
_____ Silver (Ag) reacts with moisture in the air to form tarnish.
_____ The chalkboard is magnetic.
_____ Sand and dirt are mixed in a flower pot.

9. Properties Practice
Physical property – Characteristics of substances that can be observed directly or measured with a tool without changing the identity of the substance.
Chemical property – Characteristics of substances that give them the ability to undergo a change that results in a new substance.

10. Properties Practice: Answers
__C___ Sodium (Na) is a very reactive alkali metal.
__P___ Oxygen (O) is a gas.
__C___ Wood is flammable.
__P___ A ruby is red.
__P___ Copper (Cu) conducts electricity.
__P___ Water (H2O) freezes at 0 degrees Celsius.
___C__ Iron (Fe) reacts with water to form rust.
__C___ Silver (Ag) reacts with moisture in the air to form tarnish.
__P___ The chalkboard is magnetic.
__P___ Sand and dirt are mixed in a flower pot.

11. Homework Add the following terms to you Unit 2 vocabulary list:
Valence Electrons
Chemical Property
Oxidation
Flammability
Radioactivity
Don’t forget to include:
Detailed description
Image or example
Clue or connection
Part IV of your project is due Friday!
Your answers should reflect research, not what you can copy from your notebooks!