To draw the Lewis structure of methyl fluoride (CH3F), we start by identifying the number of valence electrons. Carbon (C) has 4 valence electrons, each hydrogen (H) has 1 (and there are 3 of them), and fluorine (F) has 7 valence electrons. Therefore, the total number of valence electrons is:
- 4 (C) + 3×1 (H) + 7 (F) = 4 + 3 + 7 = 14 valence electrons
In the Lewis structure, the carbon atom is placed in the center because it is the least electronegative element and can form multiple bonds. We then connect the carbon atom to the three hydrogen atoms and one fluorine atom with single bonds. This utilizes 8 of the 14 valence electrons (2 per bond).
The remaining 6 valence electrons are then placed around the fluorine atom, completing its octet. The final Lewis structure looks like this:
H
|
H - C - F
|
H
Now, to answer the second part of the question, the central atom in this Lewis structure is carbon (C). This is because it is bonded to the other atoms (three hydrogen and one fluorine) and serves as the central point in the structure.