In a regular `B_(12)`
icosahedran : How many valence electrons are there ?

Explanation

To determine the number of valence electrons in a regular B12 icosahedron, we can follow these steps:

### Step 1: Identify the valence electrons of a single boron atom.
Boron (B) has an atomic number of 5. Its electronic configuration is:
- 1s² 2s² 2p¹

From this configuration, we can see that boron has:
- 2 electrons in the 2s subshell
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