B: e= 5
N: p=7, n=7
Fluorine: e=9
N: p=10, c= 0
Magnesium: n=12, c=2+
Aluminum: p= 13, e=13, n=14
Silicon: p=14, n=14, c= +4, -4
Sulfur: p=16, e= 16, n= 32
K: p= 19, e= 19, n= 20
The answers were derived from the formula: p= atomic number; e= atomic number; n= mass number - atomic number
