Final answer:
The mass of drink crystals that dissolved in 100mL of water to form a saturated solution is 4.0 grams, assuming the density of the solution is the same as water (1.0 g/mL).
Step-by-step explanation:
To calculate the mass of drink crystals that dissolved in 100mL of water to form a saturated solution, we should first assume the density of the solution is the same as the density of water, which is approximately 1.0 g/mL due to the low solubility of the salt. Therefore, 100 mL of water corresponds to a mass of 100 g of the solution. Given that the solution contains 4.0 g of NaCl per 100 g of solution, we can determine that the mass of the dissolved crystals in a 100 mL saturated solution is also 4.0 grams.
If we needed to calculate the molarity, we would use the formula mass of NaCl (58.44 g/mol) and the density of the solution. However, for this question, only the mass of the dissolved crystals is required, which we've already established as 4.0 grams.