Question

element lewis structure bohr model # of valence e- __ # of e- __ beryllium # of valence e- # of e-

Explanation:

Step1: Determine valence electrons for Beryllium

Beryllium (Be) has an atomic number of 4. Its electron configuration is $1s^2 2s^2$. Valence electrons are in the outermost shell, so the 2s orbital has 2 electrons. So, number of valence electrons is 2.

Step2: Determine total electrons for Beryllium

The atomic number of Beryllium is 4, and in a neutral atom, the number of electrons equals the atomic number. So, total number of electrons is 4.

Answer:

For Lewis Structure (number of valence electrons): 2
For Bohr Model (number of electrons): 4