Assuming that the density of the final solution is 1.00 g/mL, how many grams of caffeine standard do you need to add to a 500-mL volumetric flask in order to create a solution that has a concentration of 1000 ppm? Enter your answer as X.X g
Assuming that the density of the final solution is 1.00 g/mL, how many grams of caffeine...
A cup of Starbucks brewed coffee contains 15.2% caffeine by mass. What volume of this drink solution in milliliters contains 53.8 g of caffeine? (density of water is 1.00 g / mL). 2. How much caffeine (C8H10N4O2) in grams is contained in a 16 oz cup?
A student prepares a caffeine standard solution that has a concentration of 1858 ppm. To prepare a calibration curve, the student pipets various volumes of the standard solution into 50.0 mL volumetric flasks and dilutes to the fill line with water. The absorbance of each solution is measured in a 1.00 cm cuvette using the spectrophotometer and is shown in the table below. Calculate the concentration of each solution and create a calibration curve using the absorbance data provided. Based...
You are asked to prepare 500. mL of a 0.100 M acetate buffer at pH 5.00 using only pure acetic acid (MW=60.05 g/mol, pKa=4.76), 3.00 M NaOH, and water. Answer the following questions regarding the preparation of the buffer. 1. How many grams of acetic acid will you need to prepare the 500 mL buffer? Note that the given concentration of acetate refers to the concentration of all acetate species in solution. 2. What volume of 3.00 M NaOH must...
If 0.4575 g of CaCO3 were dissolved and diluted in a 300.00 mL volumetric flask (assume the density of the solution is 1.00 g/mL), what would the calcium (Ca2+) concentration be in a) molarity and b)ppm?
You are asked to prepare 500 ml of a 0 250 M acetate Puffer at pH 5.00 using only pure acetic acid (MW = 60.05 g/mol, pKa = 4.76). 3 00 M NaOH, water. Answer the following questions regarding the preparation of the buffer. How many grams of acetic acid will you need to prepare the 500 mL buffer? Note that the given concentration of acetate refers to the concentration of all acetate species in solution. What volume of 3.00...
a.) Salt solution is 12.0% NaCl by mass, with a density of 1.023 g/mL. What are the molarity, molality, and mole fraction of this solution? b.) How many grams of salt would you need to add to 500 mL of this solution to raise its mole % to 5.00?
total volume of 500 . mL In the laboratory you dissolve 18.1 g of ammonium phosphate in a volumetric flask and add water to What is the molarity of the solution? M How many milliliters of an aqueous solution of 0.137 M calcium chloride is needed to obtain 18.1 grams of the salt? mL You need to make an aqueous solution of 0.232 M aluminum nitrate for an experiment in lab, using a 125 mL volumetric flask. How much solid...
5.3307 g of Na2CrO4 (MW 161.97 g/mol) is dissolved in 1000.0 mL of water. Assuming the solution has a density of 1.00 g/mL, what is the concentration of Na (MW 22.9898 g/mol) in the solution in units of a) molarity (M)? Number b) parts per thousand (ppt)? Number ppt c) 25.0 mL of the solution is then diluted to a final volume of 500.0 mL. What is the concentration of Na* in the diluted solution in units of parts per...
A student weighs out 14.6 g of AlBrz, transfers it to a 300 mL volumetric flask, adds enough water to dissolve the solid and then adds water to the 300 mL mark on the neck of the flask. Calculate the concentration (in molarity units) of aluminum bromide in the resulting solution? Calculate the mass, in grams of sodium iodide that must be added to a 250 mL volumetric flask in order to prepare 250 mL of a 0.138 M aqueous...
How many milliliters of an aqueous solution of 0.149 M sodium sulfate is needed to obtain 6.41 grams of the salt? In the laboratory you dissolve 17.4 g of copper(II) bromide in a volumetric flask and add water to a total volume of 500 . mL. What is the molarity of the solution?