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Selenium has six valence electrons. What is the most common valence of selenium in its compounds?
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- 1. Intro to General Chemistry3h 46m
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- 23. Chemistry of the Nonmetals2h 39m
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- Ligands10m
- Complex Ions5m
- Coordination Complexes7m
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- Coordination Numbers & Geometry9m
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- Crystal Field Theory Summary8m
- Magnetic Properties of Complex Ions9m
- Strong-Field vs Weak-Field Ligands6m
- Magnetic Properties of Complex Ions: Octahedral Complexes11m
10. Periodic Properties of the Elements
Valence Electrons of Elements
Multiple Choice
How many valence electrons does a helium (He) atom have?
A
8
B
2
C
1
D
0
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검증된 단계별 안내1
Identify the element in question, which is helium (He).
Recall that valence electrons are the electrons in the outermost shell of an atom.
Determine the electron configuration of helium. Since helium has an atomic number of 2, it has 2 electrons.
Recognize that helium's electrons fill the first shell (1s orbital), which is also its outermost shell.
Conclude that helium has 2 valence electrons because both electrons are in its only shell.
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