There is no element symbolized as "M". If you find M in a chemical formula or equation, it most likely means any metal element (i.e., iron, silver, etc). There are three metals which begin with M: magnesium (Mg), manganese (Mn) and molybdenum (Mo).
I .. N:I .. I Sorry about the wierd spacing but there is a single bond on the top of the N and on the bottom
It represents the number of valence electrons in the atom.
G.N. Lewis
to find the electron dot configuration of an element simply draw dots, symbolizing valance electrons, in a way that they are farthest from each other around the symbol of the element you are using.
They can also be called Lewis Dot Structures or Diagrams, named after a scientist names Gilbert Norton Lewis
Electron dot formula tells the number of valence electrons
The formula of cyclopentane is C5H10
P..h.p
It has an octahedral shape.
.. h:c: ..
H-Cl| or H:Cl:::
H=h
linear formula
Lewis dot structure
Lewis structure, electron dot diagram, electron dot structure...
I .. N:I .. I Sorry about the wierd spacing but there is a single bond on the top of the N and on the bottom
A list of chemical elements and symbols is at this link.