unit 2: periodic table - mrs. rhee...
TRANSCRIPT
Unit 2: Periodic Table Periodic Law and Labeling
The Periodic Law
When the elements are arranged by increasing atomic number,
The Periodic Law
When the elements are arranged by increasing atomic number,
there is a periodic repetition of their chemical and physical properties.
Dmitri Mendeleev (1834-1907)
• First to notice the element's periodic repetition of properties.
• Designed the first periodic table (in1869)
Mendeleev
Mendeleev
• His periodic table was arranged by atomic mass. (our current PT is arranged by atomic number)
• He was able to predict properties of undiscovered elements.
Labeling the PT• Rows across the
PT are called periods (1-7)
• Columns down the PT are called groups or families (1-18)
Period
Column/ Family
Period
Group/Family
1
765432
67
1142 1516 17
18
43
13
8765 1211109
Groups/Families have 3 naming methods
• #1-18 • 1A-8A • Special family names
1A2A 3A 4A 5A 6A 7A
8A
Family Number Family Name Family Number Family Name
1 Alkali Metals 15 Nitrogen Family
2 Alkaline Earth Metals 16 Oxygen Family
3-12 Main Group Transition Metals 17 Halogens
13 Boron Family 18 Noble Gases
14 Carbon Family
Zigzag on the PT• Metalloids on the PT divide the metals
from the nonmetals.
• They form a zigzag (or staircase) on the PT. Memorize these 8 metalloids!
• Metals are on the left of the metalloids.
• Nonmetals are on the right (don’t forget hydrogen though!)
The Eight Metalloids: Boron, Silicon, Germanium, Arsenic, Antimony, Tellurium,
Polonium, & Astatine
What about the bottom section?
• Elements with atomic numbers 58-71 are called the Lanthanide Series. They are in period 6.
• Elements with atomic numbers 90-103 are called the Actinide Series. They are in period 7.
• These elements fit inside the main group transition metals so they are collectively called the Inner Transition Metals.
Long Periodic TableThis is what the PT would look like if the the inner
transition metals were placed inside the main group.
Inner Transition Metals
The Super Seven!• Diatomic elements are
found in nature as pairs of atoms; two identical atoms bonded together.
• The super seven (diatomic elements) are H2, N2, O2, F2, Cl2, Br2, & I2
Phases!
• 2 liquids
• 11 gases (don’t forget hydrogen!)
• the remaining are solids