Write a Lewis symbol for each atom or ion.
Solution 38E Step 1 of 5 Lewis structures: Valence electrons of the main group elements are represented as the dots surrounding the symbol of the element in Lewis structures of atoms or ions. Step 2 of 5 2 2 6 a) Sulphur (S) has atomic number= 16, thus it has this electronic configuration: 1s 2s 2p 2 4 2 2 6 2 6 3s 3p , but if it gain two electrons its new electronic configuration will be: 1s 2s 2p 3s 3p When Sulphur does that, it completes its outer shell because it has eight electrons, but it becomes an anion because it acquires 2 negative charges in form of electrons. 2- In S structure we have to represent eight dots and a 2– formal charge out of the brackets Step 3 of 5 2 2 6 b) Atomic number of Magnesium (Mg) is 12, thus it has this electronic configuration 1s 2s 2p 2 3s . Thus it has two electrons in his valence shell (the two locate in 3s orbital). Hence its Lewis structure is