2. Elements and the Periodic Table
Oct 30 / Act B16
Elements and the Periodic Table
LEARNING TARGET: I can differentiate between: elements and compounds; molecules and atoms and how they all relate to each other.
CH Q
What are the elements and how do they relate to compounds?
VOCAB:
next slide

3. uses symbols to make a chemical chemical formula
molecule
compound
two or more of the same atom bonded together
two or more DIFFERENT atoms bonded together

4. alkali and alkaline earth metals
DISCUSSION
Looking at your copy of the Periodic Table, Discuss and identify:
The two families that seem most alike
Which family seems the most different from the others
What kind of properties can you use to distinguish groups of elements
alkali and alkaline earth metals
noble gases
reactions with others
solid, liquid or gas

5. PROCEDURE: Read on pg. B-22-29 and Stop and Thinks!
PROCEDURE AND DATA
MATERIALS:
PROCEDURE: Read on pg. B and Stop and Thinks!
No summary today!
DATA: WS Periodic Table of Elements
Notes in journal

6. That there were only four (4) elements (earth, air, fire, water)
DISCUSSION
Stop and Think 1
1. In what way were the ancient Greek philosophers right about elements?
2. In what way were the ancient Greek philosophers wrong?
The early Greeks were right, Everything was made of elements
That there were only four (4) elements (earth, air, fire, water)

7. Early Greeks thought that all matter (stuff) in the Universe was made of only Four Earth Elements:
water
*water comes out of you when you sweat, out of grapes, apples, etc.
earth (dirt)
*can’t grow plants without it
fire
*is obviously there and changes things
It’s “obvious” that all things you see can be made in different combinations of these four Earth Elements, right??
air
*you can feel
wind push you

8. Get it – the four Earth Elements?!
Here’s the Greeks’ first Periodic Table of the Elements
Get it – the four Earth Elements?!

9. 1. How did Mendeleev build on other scientists’ work?
Stop and Think 2
1. How did Mendeleev build on other scientists’ work?
2. How did other scientists build on Mendeleev's work?
He analyzed the data other scientists collected about properties of the 63 elements that were known at the time
They predicted and found other elements based on the periodic table and revised the arrangement of the table to fit new discoveries.
Scientists still use the table first arranged by Mendeleev to predict the properties and existence of newly created elements.

10. DISCUSSION Stop and Think 3
1. Use the Periodic Table of the Elements on the next page to decide whether each of the following is a metal or a nonmetal:
lithium (Li)
carbon (C)
sulfur (S)
calcium (Ca)
titanium (Ti)
bromine (Br)
metal
non-metal
non-metal
metal
metal
non-metal

11. Group 2 - alkaline earth metal
DISCUSSION
Stop and Think 4
1. Find magnesium on the Periodic Table:
- What is magnesium’s chemical symbol?
-What family does magnesium belong to?
- Is magnesium a solid, a liquid, or a gas?
Based on its family, would you expect magnesium to be very reactive, somewhat reactive or not reactive at all? Explain. Mg
Group 2 - alkaline earth metal
solid
very reactive
alkaline earth metal

12. DISCUSSION Stop and Think 5
1. What are two ways that compounds are different from the elements that form them? 1.
elements = made of one kind of atom
compounds = made of molecules that contain more than one kind of atom
Compounds have different Ph+Ch properties than elements that make them

13. Na (sodium), H (hydrogen), C (carbon) and O (oxygen)
Stop and Think 6
1. The chemical formula for baking soda is NaHCO3.
- What elements are in baking soda?
- How many of each kind of atom is represented by the formula for baking soda?
Na (sodium), H (hydrogen), C (carbon) and O (oxygen)
Na = 1, H = 1, C = 1 and O = 3

14. DISCUSSION
Using the Periodic table in the book and your team, color your copy of the Periodic Table with the following colors:
Alkalai Metals – light green
Noble Gases – light blue
Alakline Earth Metals – light purple
Non-metals – orange
Halogens – yellow
Transition Metals – light red
Make a key on the back to identify later

16.  Benfey's spiral periodic table.

18. - Discuss and answer Q 1 - 4 on pg. B- 30
ANALYSIS
- Discuss and answer Q on pg. B- 30
ANS CH Q
What are the elements and how do they relate to compounds? A:
same atoms = element
>2 atoms = molecule
>2 DIFFERENT atoms = compound
HOMEWORK
Finish Analysis Qs
Periodic table

19. ANALYSIS: 1 HW from last class Debrief – check your answers
Substance
Chemical Formula
# atoms in molecule
hydrogen peroxide
H2O2
H = 2, O = 2
carbon dioxide
CO2
C = 1, O = 2
sucrose (sugar)
C12H22O11
C = 12, H = 22, O = 11
alanine (amino acid)
C3H7O2N
C = 3, H = 7, O = 2, N = 1
oleic acid (fat)
C12H24O2
C = 12, H = 24, O = 2