Answer:
1s² 2s²2p³
Explanation:
If the atom has seven electrons, it is Element 7 (nitrogen).
In the Periodic Table, you count the electrons in all the subshells up to
No. 7.
In the first Period, you have filled the 1s level (2 electrons).
In the second Period, you have filled the 2s subshell (2 electrons) and put three electrons in the 2p subshell.
Thus, the electron configuration is
1s² 2s²2p³
Note how the superscripts tell you the number of electrons in each subshell: <em>2 + 2 + 3 = 7</em>.
Answer:
Choose the least electronegative atom other than H.
Explanation:
A Lewis structure consists of <em>terminal atoms</em> and one or more <em>central atoms</em>.
H can be <em>only a terminal atom</em> because it can form only one bond.
So the central atom must be either C or O.
The central atom is the less electronegative atom: C.
So, start the Lewis structure with a central C atom.
Then attach an O atom to get C-O.
Finally, attach the H atoms.
The condensed formula often gives you a clue where they go.
The formula CH₃OH implies that there are 3 H atoms on C and one on O.
The connectivity of the atoms is then as in the diagram below.
