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How many valence electrons does beryllium (Be) have?
A
8
B
6
C
4
D
2
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1
Identify the element in question, which is beryllium (Be).
Determine the atomic number of beryllium, which is 4, meaning it has 4 electrons in total.
Recall that valence electrons are the electrons in the outermost shell (energy level) of an atom.
Write the electron configuration of beryllium: \$1s^2 2s^2$.
Count the electrons in the outermost shell (the second shell), which are the valence electrons. For beryllium, this is 2 electrons in the \$2s$ orbital.