Separating a Mixture of Compounds Exp. No. 2

Separating a Mixture of Compounds
Exp. No. 2 name Chemistry 145
February 2, 2014
I. Purpose
The purpose of this experiment was to separate this mixture into components, determine the mass and percentage of each component. In addition to test the accuracy of an alternative method of subtraction to find the mass of the sodium chloride directly. Start with a mixture of sand (SiO2), sodium chloride (NaCl), and ammonium chloride (NH4Cl), and use these separation processes: sublimation filtration evaporation First "sublimate" the ammonium chloride (NH4Cl); heat the mixture until the ammonium chloride (NH4Cl) passes into the gaseous phase. The remaining solid will be a mixture of the remaining two compounds, sodium chloride (NaCl) and sand (SiO2); these compounds do not undergo sublimation. Next, add water. Sodium chloride (NaCl) (and any small amount of ammonium chloride that may have been retained) dissolves in water, sand (SiO2) does not. "filter" the entire mixture; this allows the water, in which the sodium chloride (NaCl) is dissolved, to pass through, but not the sand. Sodium chloride (NaCl) is now separated from the sand (SiO2).
II. Experimental Method
Equipment: two clean 50 mL beakers, evaporating dish, thermometer, Bunsen burner, and scale
Chemicals: water and Powered mixture of (SiO2), (NaCl), and (NH4Cl)

Part 1: Sublimation of Ammonium Chloride (NH4Cl)
Using a scale, weight and record the mass of the empty evaporating dish. Add 10 g of the Powder Mixture to the evaporating dish. Weigh and record the total mass (evaporating dish plus powder mixture). Then remove the evaporating dish from the scale. Take a thermometer and attached it onto the evaporating dish. The thermometer will turn on and display room temperature, 21.5 °. Take a Bunsen burner and place it on the workbench. Place the evaporating dish on the Bunsen burner, a white vapor will rise from the dish. Continue heating for another minute after the vapors is seen to complete