Chemistry
posted by Ellen on .
A 25.00mL sample of a household cleaning solution was diluted to 250.0mL in a volumetric flask. A 50.00mL aliquot of this solution required 40.38mL of 0.2506 M HCl to reach a bromocresol green end point. Calculate the weight/volume percentage of NH3 in the sample. (Assume that all the alkalinity results from the ammonia.)
Can someone please explain how to get the volume when calculating for the weight/volume percentage. I know how to get the weight but don't know how to get the volume for this question. Please explain it throughly. Thanks.

You took a 25.00 mL sample and diluted t 250.0 mL and titrated a 50.00 mL aliquot. You have the weight in the 50.00 mL sample. The weight in the original 25.00 mL sample is weight in titrated sample x (250/50) = ? Now you have the weight in the original 35.00 mL sample and that is the volume you use.