**I am adding 50 gm of sugar to 500 ml of water. How do I calculate the density of the sugar solution? (Is it) 50 gm/500ml or 50/(volume of water displaced by the sugar)?**

Jennifer Schmahl-
The density of the solution will be mass
*of solution*divided by volume*of solution*.- 50 g/500 mL isn't correct because the volume of the solution isn't 500 mL.
- 50 g/(volume of water displaced by the sugar) isn't correct because you're comparing a sugar mass to a water volume.

To determine the solution's density, weigh a precisely measured volume of your solution, and divide the mass of solution by the volume of solution.

**You must measure the volume of solution**to obtain the density. You can't calculate the density of the solution with just the data you've given above. You can get a crude estimate (e. g., if you assume the volume of the dissolved sugar is negligible compared to the volume of the water, the density is roughly (50 g sugar + 500 g water) / 500 mL solution. But the assumption isn't correct- try it yourself!) Even if you happened to know what the volume of the added sugar was, the volume of a solution is NOT the volume of the solute plus the volume of the solvent.

General Chemistry Online! Can I get a solution density from the solute mass and solvent volume?

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Last Revised 08/17/15.URL: http://antoine.frostburg.edu/chem/senese/101/solutions/faq/print-solution-density-from-concentration.shtml