Unit 4 - The Periodic Table - Introduction & Groups Flashcards
1
Q
Why is the Periodic Table used?
A
Determines how chemicals will react or behave
2
Q
Who was Dmitri Mendeleev? (5)
A
- Arranged elements by increasing X
- First usable PT
- Noticed elements w/ similar chem & phys prop.
- Identified regular, predictable & periodic intervals of properties
- Predicted existence of elements not yet discovered (boron & silicon)
(X = atomic mass)
3
Q
How was the atomic number discovered? (3)
A
- Henry Moseley (student of Rutherford)
- Used X - Rays
- Repositioned elements on modern PT
4
Q
What are Groups? (4)
A
- Vertical Columns
- Same Group = Same VE
- Same group = Same Reaction & Bonding (VE)
- Similar properties
Group 15 = 5 VE
Group 2 = 2 VE
Group 18 = 8 VE (except He)
5
Q
What are Periods? (2)
A
- 7 Horizontal Rows
- Period Num. = Num. of Principle EL
6
Q
What are alkali metals? (3)
A
- Group 1
- Not found free in nature
- Because it is the most reactive metals
7
Q
What are Alkaline Earth Metals? (3)
A
- Group 2
- High reactive (less than G1)
- Found in rocks on Earth’s crust
8
Q
What are Transition Metals? (5)
A
- Group 3 - 12
- Form Colored Solutions
- Don’t form normal rules of VE
- Good conductors of electricity
- Malleable & Ductile
9
Q
Definition of Malleable
A
Easily bended/hammered
10
Q
Definition of Ductile
A
Stretched into a thin wire without breaking
Ex: Copper, often used in electrical wiring
11
Q
What are Lanthanides (La) & Actinides (Ac)? (2)
A
- Two rows at the bottom of the PT
- Rare earth metals
12
Q
What are non - metals? (4)
Location, Properties, Form
A
- Fount on the right side of the PT
- Brittle, Solid or Gases (Bromine is liquid)
- Form ions of a negative charge
- Don’t Conduct Electricity
13
Q
What are Halogens? (3)
A
- Group 17
- Most reactive nonmetals
- Most are poisonous
14
Q
What are Noble Gases? (4)
A
- Group 18
- Full outer Valence Shell (8)
- Unreactive
- Gases at room temp.
15
Q
Definition of Families (2)
A
- 1 or several groups
- Share physical and chemical properties
