Week 21
Lessons
Video
Summary
FAQ
Comments
Quiz
Lessons 1
Text
Lessons 2
Text
Lessons 3
Text
Element
Symbol
Atomic Number
Atomic Weight
Hydrogen
H
1
1.008
Helium
He
2
4.0026
Carbon
C
6
12.011
Oxygen
O
8
15.999
Iron
Fe
26
55.845
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