How do you convert milligram per liter to percent?
You cannot. The milligram is a unit of weight and the litre a unit of volume. In the case of water only a litre happens to weigh a kilogram and therefore a milligram of water is 0.1 % of a kilogram and 0.1 % of a litre.
milligram divided by 1000 will give you grams, now use the molecular weight to get the number of moles. next divide dl by 10 to get liters. now you got moles per liter :) There is another simple way to convert miligram per dl into milimoles: 1gm/dl-multiply by 0.055= mm/litre and reverse mm/L divided by 0.055=mg/dl