Caffeine in chocolat
There really isn't that my much caffeine
in chocolate, but there is some.
There is also a related substance, theobromine. The half life of caffeine can range from 3-12 hours, meaning that with a single dose of chocolate in the morning at 7am, if you are on the 12-hour side, you will still have 1/2 of the caffeine around. Given the small amounts, it is not likely that it would keep you awake.