Answer Happy

Problem 1. [Objectives: Understanding physical water quality parameters definition/analysis] [Understanding the difference between TDS & SS, ability to extrapolate to mg/lit] You are asked to measure Total Dissolved Solids (TDS) concentration of Lake Merced. You walk to the lake and take a sample then go to the lab and weigh an empty evaporating dish. The weight is 40.525 grams. You filter the water of the sample you have taken and pour 100 ml of the filtered water onto the empty pre-weighed dish, place it in an oven and evaporate all the water for one hour at 104 degrees Centigrade (standard method). You measure the weight of the dish plus the dried residue, and it is: 40.545 grams. a. The TDS is calculated to be-..... ---mg/liters. b. You are required to compare this value with the MCL (Maximum Contaminant Limit) specified in the Secondary Drinking Water standards. That value is-------- ------mg/liters. c. In your opinion, does this water comply with this standard in terms of TDS? (please give an answer of yes or no and say why in one sentence)---