I need help with this question... phenobarbital elixir contains 2 grams in 1 liter of elixir. How many milligrams of phenobarbital are contained in 1 teaspoon of elixir?

To solve this problem, all we need is the conversion factor. We know that there are: 1 liter = 202.884 teaspoons   Therefore the mass of Phenobarbital is: mass = (2 grams / 1 Liter) * (1 teaspoon) * (1 Liter / 202.884 teaspoons) mass = 0.00986 g = 9.86 x 10^-3 g = 9.86 mg