Chem notes

1
Chem notes

• Section 5.4

2
The Periodic Table

• Mid-1800s about 70 elements had been
  discovered.
• Dmitri Mendeleev (Russian chemist) organized
  elements

3

• Listed elements in columns or order of increasing
  atomic mass.
• Arranged columns so elements with similar
  properties were side by side.
• Left blank spaces for unknown elements with
  appropriate properties and masses.
• Eventually these elements were discovered with
  the predicted properties

4

• In 1913 Henry Moseley arranged elements in a
  table
• By order of increasing atomic rather than
  atomic mass.

5
Modern Periodic Table

• Atomic shown centered above the elements
  atomic symbol.

6
Modern Periodic Table

• Atomic shown centered above the elements
  atomic symbol.
• Atomic mass and element name below symbol

7
Modern Periodic Table

• Atomic shown centered above the elements
  atomic symbol.
• Atomic mass and element name below symbol
• In order in increasing atomic from left to
  right and top to bottom

8
Periods

• Horizontal rows 7 periods

9
Periods

• Horizontal rows 7 periods
• The number of elements range from 2 in period 1
  to 32 in period 6

10
Periods

• Horizontal rows 7 periods
• The number of elements range from 2 in period 1
  to 32 in period 6
• Periodic Law
• When elements are arranged in order of increasing
  atomic , there is a periodic repetition of their
  physical and chemical properties. (elements with
  similar chem/phys properties end up in same
  column)

11
Groups (or families)

• Vertical columns 18 groups

12
Groups (or families)

• Vertical columns 18 groups
• Elements in any group have similar properties.

13
Groups (or families)

• Vertical columns 18 groups
• Elements in any group have similar properties.
• Each group identified by a number and either
  letter A or B.

14
Groups (or families)

• Vertical columns 18 groups
• Elements in any group have similar properties.
• Each group identified by a number and either
  letter A or B.
• Group A elements 1A-7A Group 0 called
  representative elements

15
Metals

• Properties
• High electrical conductivity

16
Metals

• Properties
• High electrical conductivity
• High luster when clean

17
Metals

• Properties
• High electrical conductivity
• High luster when clean
• ductile

18
Metals

• Properties
• High electrical conductivity
• High luster when clean
• Ductile
• Malleable

19
Metals

• Properties
• High electrical conductivity
• High luster when clean
• Ductile
• Malleable
• Solid at room temperature (except for Mercury)

20
Metals

• On left side of periodic table (except for H)
• Group 1A Alkali Metals

21
Metals

• On left side of periodic table (except for H)
• Group 1A Alkali Metals
• Group 2A Alkaline Earth Metals

22
Metals

• On left side of periodic table (except for H)
• Group 1A Alkali Metals
• Group 2A Alkaline Earth Metals
• Group B Elements
• Transition metals
• Inner transition metals (rare earth metals)

23

• Approximately 80 of all elements are metals.

24
Non-Metals

• Properties
• Generally non-lustrous

25
Non-Metals

• Properties
• Generally non-lustrous
• Poor conductors of electricity

26
Non-Metals

• Properties
• Generally non-lustrous
• Poor conductors of electricity
• Can be solid, liquid or gas at room temp.

27
Non-Metals

• Occupy upper right corner of periodic table.
• Group 7A halogens
• Group 0 noble gases (inert gases)

28
Metalloids

• Includes most elements along stairstep line which
  separates metals from non-metals.

29
Metalloids

• Includes most elements along stairstep line which
  separates metals from non-metals.
• Have properties of both metals and non-metals