00:01
For this question, we'll use du to represent the degree of unsaturation.
00:12
Now, to calculate the degree of unsaturation, that's equal to 1ā2 times 2 times the carbons, 2 carbons plus two plus the number of nitrogen atoms minus the number of halogen atoms minus the number of hydrogen atoms so for a we have two rings and one double bond so our degree of unsaturation here is three so three is equal to one half and then we have eight carbons so eight to times 2 plus 2 minus the, there's no nitrogens, there's no halogens, minus the number of hydrogens.
01:27
So solving for the number of hydrogens here, we get 12 hydrogen atoms for a.
01:35
For b, we're told that we have two double bonds.
01:41
The degree of unsaturation here is 2.
01:50
So 2 is equal to 1 1 .5.
01:53
And we have 7 carbon, so 7 times 2 plus 2.
02:00
And we have a nitrogen, so minus 1 minus hydrogen.
02:05
And the number of hydrogen atoms here works out to be.....