How many milliliters are in a gram?
If you wish to know the weight in grams of a milliliter of a substance, then you must know the density of the substance.
For heavier things, I.E. heavy metal alloys, density needs to be taken into consideration. However, for a basic Chemistry problem, or Cooking conversion (butter, bullion) 1g = 1mL.
The correct and complete answer is as follows:
Mass = Density x Volume
Milliliter is a volume and Gram is a mass. There is no set number since it varies depending on the matter you wish to convert. If you are converting water, they are equal.