Chemistry Lab Report Example

805 Words4 Pages
Decomposing baking soda ※ Purpose: To determine the percent yield of sodium carbonate from a decomposition reaction and to determine the percentage of sodium hydrogen carbonate in an unknown mixture. ※ Procedure: (a) Percent yield of Na2CO3 from baking soda 1. Weigh a baker, and record the mass. Add baking soda, NaHCO3, and reweigh. 2. Weigh the baker containing sodium carbonate residue. Find out the mass of Na2CO3 3 calculate the theoretical yield of sodium carbonate, Na2CO3, from the pure baking soda that was heated. Find the percent yield of sodium carbonate (B) percentage of NaHCO3 in an unknown Mixture 1. Obtain an unknown sample containing baking soda. Record the unknown number. 2. Repeat steps 1---3 as in procedure A, substituting the unknown mixture for the pure baking soda. 3. Calculate the mass of baking soda,NaHCO3 , and find the percentage of baking soda in the unknown mixture. ※ Data and observations (a) Table 1: Percent yield of Na2CO3 from baking soda Percent yield of Na2CO3 from baking soda Trial 1 Trial 2 Mass of flask + NaHCO3 95.12 g 93.45g Mass of flask 94.15g 92.03g Mass of NaHCO3 0.97g 1.42g Mass of flask + Na2CO3 95.01g 93.12g Mass of Na2CO3 (actual yield) 0.86g 1.09g Mass of Na2CO3 (theoretial yield) 0.61g 0.90g % yield of Na2CO3 140% 120% (b) Table 2: Percent of baking soda in Unknown Percentage of NaHCO3 in an unknown mixture # C Trial 1 Trial 2 Mass of flask + unknown mixture #C (before heating) 95.81g 94.85g Mass of flask 94.15g 92.03g Mass of unknown mixture (before heating) 1.66g 2.82 g Mass of flask + residue (after heating) 95.20g 93.80g Mas of H2CO3 (H2O + CO2) (after heating) 0.61g 1.05g Mass of NaHCO3 in the unknown mixture 1.65g 2.84g % of NaHCO3 in the unknown mixture 99.0% 101% ※ Calculations For table 1: Theoretical yield of Na2CO3 for trial 1

More about Chemistry Lab Report Example

Open Document