The Periodic Table

1. 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 (1,2, 13-18) are known asRepresentative Elements • 1B-8B(3-12) 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 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. 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. 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