1. By: Mrs. Rieseck-Terracio
The Periodic Table
By: Mrs. Rieseck-Terracio

2. What is the Periodic Table?
Periodic Table: A chart that organizes all known elements by increasing atomic number, there is a periodic repetion of their chemical and physical properties.
Helps organize your knowledge of Chemistry.

3. Modern Periodic Table

4. Development of the Periodic Table

5. Antoine Lavoisier Late 1790’s Compiled list of elements 23 elements
Many known since ancient times
Silver
Gold
Carbon
Oxygen

6. In the mean time: 1800’s brought about an explosion of new elements.
Invention of spectrometer used to identify new elements.
Industrial revolution in mid 1800’s many new chemistry based industries:
Petrochemicals
Soaps and dyes
Fertilizers

7. In the mean time: 1870 now are 70 elements known.
Chemist overwhelmed with all the new information.
Need a tool for organizing information.
1860 chemist agreed on a method of determining atomic masses of elements.
With reproducibility came research between mass and elemental properties really began.

8. John Newlands English Chemist 1864
Proposed an organization of elements
Arranged by atomic mass.
Every 8th element had repeating properties.

9. John Newlands Law of octaves. Was not widely accepted.
Did not work for all elements.
Term “octave” to musical.
In a couple of years was shown to be on the right path.

10. Meyer and Mendeleev 1869 German chemist Lothar Meyer.
Russian chemist Dmitri Mendeleev
Both demonstrated a connection between atomic mass and elemental properties.
Mendeleev given more credit.

11. Dmitri Mendeleev Atomic mass Columns of similar properties.
1st periodic table.
Left blank spaces
Said they were for undiscovered elements.

12. Dmitri Mendeleev Not completely correct.
Some newly discovered elements didn’t “fit”.

13. Mendeleev’s Table

14. Henry Moseley
1913
English chemist
Discovered the Atomic Number.

15. Henry Moseley 1913 English chemist Discovered the Atomic Number.
Rearranged the periodic table according to Atomic Number.
Problems were solved.

16. Periodic Law
Periodic Law: States that when the elements are arranged by increasing atomic number’ there is a periodic repetition of their chemical and physical properties.

17. Modern Periodic Table Arranged by increasing atomic number.
Consists of boxes, usually containing:
Element symbol
Atomic number
Atomic mass

18. Just a Sample

19. Modern Periodic Table Boxes arranged in Groups
1A-8A are known as Representative Elements
1B-8B are known as Transition Elements
Boxes also arranged in Periods
7 periods

20. Representative Elements
Representative Elements: Groups of elements in the modern periodic table that are designated with an A (1A through 8A) and possesses a wide range of chemical and physical properties.

21. Transition Elements
Transition Elements: Groups of elements in the modern periodic table that are designated with a B (1B through 8B) and are further divided into transition metals and inner transition metals.

22. A way of organizing & classifying elements
Arranged in rows and columns

23. Columns
The vertical (up and down) columns of the periodic table (there are 18) are called groups or families.
Elements in the same group or family have similar characteristics or properties.

24. Rows The horizontal rows of the periodic table are called periods.
Elements in a period are not alike in properties.
The first element in a period is usually an active solid, and the last element in a period is always an inactive gas.

25. Rows
Atomic size (number of protons) decreases from left to right across a period.
Atomic mass (number of protons) increases from left to right across a period.

26. Rows
Metals are on the left
Non-metals are on the right

27. ALKALI METALS very reactive metals that do not occur freely in nature
malleable, ductile, good conductors of heat and electricity.
softer than most other metals
can explode if they are exposed to water

28. not found free in nature
ALKLINE EARTH METALS
metals
very reactive
not found free in nature

29. TRANSITION METALS
ductile and malleable, and conduct electricity and heat
iron, cobalt, and nickel, are the only elements known to produce a magnetic field.

30. RARE EARTH ELEMENTS
many are man-made

31. are ductile and malleable
OTHER METALS
are ductile and malleable
are solid, have a relatively high density, and are opaque

32. METALLOIDS have properties of both metals and non-metals
some of the metalloids, such as silicon and germanium, are semi-conductors. This means that they can carry an electrical charge under special conditions. This property makes metalloids useful in computers and calculators

33. NON-METALS not able to conduct electricity or heat very well
very brittle, and cannot be rolled into wires or pounded into sheets
exist in two of the three states of matter at room temperature: gases (such as oxygen) and solids (such as carbon).
have no metallic luster, and do not reflect light.

34. HALOGENS
"halogen" means "salt-former" and compounds containing halogens are called "salts"
exist in all three states of matter:
Solid- Iodine, Astatine
Liquid- Bromine
Gas- Fluorine, Chlorine

35. NOBLE GASES
do not form compounds easily