1. Organization of Matter

2. S1-2-03 Define element and identify symbols of some common elements.
S Investigate the development of the periodic table as a method of organizing elements.
S Relate the reactivity and stability of different families of elements to their atomic structure.
Vocabulary & People
Period Non-metals Group
Family Alkali metals Earth metals
Chalcogens Halogens Noble gases
Mendeleev

3. Elemental symbols originated from a Greek or Latin root word
Modern Symbols
Alchemist Symbols
Dalton Symbols
Antimony Sb
Arsenic As
Bismuth Bi
Carbon C
Copper Cu
Gold Au
Iron Fe
Lead Pb
Mercury Hg
Silver Ag
Sulpher S
Tin Sn
Zinc Zn

4. Russian scientist and professor
Mendeleev (1870)
Russian scientist and professor
Arranged the 63 elements by atomic mass
Noticed a repetition of properties (periodicity)
Called the pattern of properties “Periodic Law”
Mendeleev (correctly) predicted the mass of elements yet to be discovered and left spaces open for them

5. Repetition of properties (periodicity) became more clear
Moseley (1913)
Experiments showed proton number was a better method to organize the elements.
Repetition of properties (periodicity) became more clear
Modern Periodic Law:
“The properties of elements are a periodic function of increasing atomic number”
We know now that most element properties are due to the number of valence electrons – luckily electron and proton numbers are equal

7. M e t a l s The Periodic Table contains metals and non-metals.
A staircase separates metals from non-metals.
Non- metals
M e t a l s

8. Element with properties opposite to those of metals (brittle, dull…)
Rows of the periodic table are called periods.
Elements in periods do not have similar properties
Left to right
Elements change from metals to non-metals
Non-metal
Element with properties opposite to those of metals (brittle, dull…)
periods

9. Family names and locations need to be memorized
Columns of the periodic table are called groups.
Elements in groups have similar properties
A family is a group with a specific name:
Family names and locations need to be memorized
GROUP
Alkali metals
Alkaline Earth metals
Chalogens
Halogens
Inert (noble) gases

10. Older tables have an old label system for columns with Roman numerals – new tables just number them 1 through 18

16. Simplest atomic structure - only 1 e- and 1 p+
Hydrogen*
Group 1
Non-metal gas
1 valence electron
Simplest atomic structure - only 1 e- and 1 p+
Highly chemically reactive
The placement of hydrogen is only because of its structure - 1 proton… Sometimes a table will have it raised above the Alkali Metals to avoid confusion

17. What trends (“periodicity”) have you found?

18. The Octet Rule of Chemical Reactions
Atoms with a FULL outer orbit are very stable
Chemical reactions happen when atoms work together to try to get a full valence orbit
Atoms will acquire a full outer shell in 3 ways:
Give away an e- to another atom
Take an e- from another atom
Share an e- with another atom
We’ll skip this one until next year

19. + Sodium atom: Sodium ion: 11 p+ 11 p+ 11 e- 10 e- Na Na +
Once a neutral atom gains or loses e- to be more stable it is called an ion

20. - Chlorine atom: Chlorine ion: 17 p+ 17 p+ 17 e- 18 e- Cl Cl -
Notice the ion has a charge associated with it based on the number of e- lost or gained

21. 2+
Calcium atom:
20 p+
20 e- Ca
Calcium ion:
20 p+
18 e-
Ca 2+

22. 3-
Nitrogen atom:
7 p+
7 e- N
Nitrogen ion:
7 p+
10 e-
N 3-

23. Increasing Reactivity
The LESS electrons needed, the GREATER the chemical reactivity of the element
Increasing Reactivity
A Chemical Reaction
Movement of electrons between combining atoms that results in the formation of a
NEW substance.

24. A new substance is formed
Working together to become more stable is what binds atoms (now called ions) together to make compounds.
A new substance is formed - +
explosive metal
toxic gas
Salt!

25. CAN YOU ANSWER THESE QUESTIONS? S1-2-06
How is the Periodic Table organized for the elements and what trends exist?
S1-2-03
What are the symbols of the first 20 elements and other common ones?
S1-2-08
Why do families react differently during chemical reactions?
Vocabulary & People
Non-metals Period Group
Family Alkali metals Earth metals
Chalcogens Halogens Noble gases
Mendeleev