GRAVIMETRIC ANALYSIS OF SULFATE

GRAVIMETRIC ANALYSIS OF SULFATE Observation: On addition of 6mL of 1M of lead (II) acetate to the coordination compound (sulfate), there was a color change from clear blue to pale blue. On subsequent addition of drops of lead (II) acetate to the product, no precipitation was observed indicating that the reaction had proceeded to completion. Data: Table 1: Gravimetric Analysis of Sulfate Trial 1 Trial 2 Actual mass of the sample 1.02 g 0.99 g Mass of filter paper 1.28 g 1.28 g Mass of the precipitate collected + filter paper 7.43 g 7.47 g Calculation: Mass of precipitate = (mass of the precipitate + filter paper) – mass of filter paper (7.43 – 1.28) g = 6.15g Coordination compound mean = (1.02 + 0.99)/2=1.005 g PART B: VOLUMETRIC ANALYSIS OF NH3 Observations On titration of NH3 with standard HCL, the methyl orange indicator changed from deep blue to green and then to colorless at the equivalence point. Data Table 2: Volumetric analysis of NH3 Trial 1 Trial 2 Weight of the compound 1.03 g 1.01 g Standard HCL concentration 6.0 M 6.0 M Volumes of HCL used No value was provided No value was provided Calculation Mean weight of the compound used = trial 1 value + trial 2 value (1.03 + 1.01) g = 1.02 g Error checking to see if the values agree by 1% Volume of HCL used/ mass of the compound titrated. (X) /1.02 g = XX value PART C: SPECTROPHOTOMETRIC ANALYSIS OF COPPER (II) ION Data Table 3: Spectrophotometric Analysis of Copper (II) ion Sample number Mass of Compound (g) Volume of 1M HNO3 Absorbance 5 8.8 100 No value 6 12.7 100 No value DISCUSSION Part A: Gravimetric Analysis of Copper Sulfate The filter was used to separate the filtrate from the solution using the gravitational method. Progression to completeness was proved by the addition of drop lead (II) acetate to the wall of the reaction tube and carefully watched for precipitation as the acetate hit the clear solution. The accurate mass of the filter paper and the precipitate was measured. The calculated mass of the precipitate was 6.15g, but this was not pure sulfate per se. The use of coordination I chemistry is important for three main reasons: - The periodic table is mostly composed of metals that form complexes - In industrial applications, they are used for control reactivity - They are important to biochemical processes The coordination compound here is copper ii sulfate Coordination compound mass used in this experiment= 1.005 g 10ml of 6M nitric acid 5mL of 1M lead (ii) acetate Part B: Volumetric Analysis of Nh3 A simple stoichiometry relation between ammonia and HCL from the simple neutralization reaction can be obtained as follows: NH3 + HCL ? NH4CL The volume of HCL used in titration was XXX.