Prepare 1.0 L of a 50.00 ppm iron solution from the solid Fe(NH4)2(SO4)2 of the 80.0% purity. Clearly describe how to prepare this solution. If done Chlorimetric iron analysis using the calibration curve method, specify the form of preparation of 100.0 ml of each of the following standard solutions with contents of 1.00, 5.00, 15.00 and 20.00 ppm of Fe respectively from the solution mother (It suppose that the answers are:  0.3180, 2.00, 10.00, 20.00, 30.00 and 40.00 ml of the mother solution and dilute exactly to 100.0 mL with deionized water)

A 1.8M HCl solution was standardized against 1.4g sodium carbonate Na2CO3  (MW = 106g/mol) . The Na2CO3 standard required 13.5 mL of the HCl solution to completely react up to the indicator endpoint. Two chemists prepared their samples by taking 12.0-mL aliquots of each household ammonia solution and diluting it to 25.0 mL. With the same titrant and indicator, Chemist #1’s ammonia solution required 15 mL of the standardized titrant, whereas, Chemist #2's ammonia solution required 35 mL of the same titrant. Write the balanced equation for the analyte and the titrant Solve for the exact concentration of the HCl titrant in molarity. What are the respective concentrations of ammonia of Chemist #1's sample and Chemist #2's samples in Molarity?

A mineral in a fine state of division (0.6324 g) was dissolved in 25.0 mL of 4.0 mol / L boiling HCl and diluted with 175.0 mL of H2O containing two drops of methyl red indicator. The solution was heated to 100 ° C and a heated solution containing 2.00 g of (NH4) 2C2O4 was added slowly to precipitate CaC2O4. Next, NH3 6.0 mol / L was added until the indicator changed from red to yellow, indicating that the liquid was neutral or slightly basic. After slow cooling for 1 hour, the liquid was decanted, the solid transferred to a crucible and washed five times with 0.10 wt% (NH4) 2C2O4 solution, until no Cl- was detected in the filtrate with the addition of AgNO3 solution. The crucible was dried at 105 ° C for 1 hour and then taken to an oven at 500 ° C ± 25 ° C for two hours. The mass of the empty crucible was 18.2311 g. The crucible mass with CaCO3 (s) was weighed 5 times to an average of 18.5467 g. Determine the percentage, by mass, of Ca in the mineral. Ca (40.078 g / mol); C (12.01078…

A sample of dicing salt was to be analyzed for chloride content using Fajan's method. A 1.1034g sample of the deicing salt was weighed into an Erlenmeyer flask and 50 mL of water, 0.1 g of dextrin, and 5 drops of dichlorofluorescein indicator was added to the flask. It took 39.44 mL of 0.5042 M silver nitrate to reach the endpoint of the titration. What is the % chloride in the sample, reported with the correct number of significant figures? A.63.889% C. 63.90% B. 63.888% D. 63.9%