00:01
For part a, if we count the number of electrons, we have 12.
00:06
We have two in this bond.
00:08
So 2, 4, 6, 8, 10, 12.
00:13
But in reality, for these elements, we only have a total of 10 valence electrons since carbon has 4, nitrogen has 5, and hydrogen has 1.
00:21
So what we can do is we will remove one of the electrons from the nitrogen, so it only has one lung pair, and take this lump pair to create a triple bond between the carbon and the nitrogen.
00:36
So this allows the nitrogen to have a full octet and the carbon to have a full octet, and we've reduced the number of electrons by two since we only have 10 and not 12.
00:46
For part b, the mistake is that we have a hydrogen -to -carbon double bond.
00:52
Hydrogen can only hold two electrons in its balance shell, so we will fix this by reducing that to a single bond.
01:02
And this uses two, four, six, eight electrons.
01:05
But since each carbon has four electrons and hydrogens have one, we need a total of 10 valence electrons to form a lewis structure.
01:12
So the remaining two electrons will become a triple bond between the carbons.
01:16
So now the carbons have a full octet and the hydrogens, i only have two valence electrons.
01:21
For part c, this structure gives us to 4, 6, 8, 10, 12 electrons.
01:28
But in reality, we need 16 for these atoms, so what we will do is the oxygens will remain the same, and we need to complete the octets of the oxygens and of our central atoms.
01:40
We will create two double bonds.
01:43
And this allows us to add two or four more electrons by adding two more bonds...