Iron Spectrophotometric Lab
ESTIMATION OF IRON IN IRON ORE-SPECTROPHOTOMETRIC METHOD
By: Taylor Villari
Experiment conducted on 7/22/13
Components of each test tube examined in the spectrophotometer Trial | Volume of Iron solution (mL) | Micrograms of Iron | Volume of 10% sodium acetate | Volume of 0.1% o-phenanthroline | Volume of water (mL) | 1(blank) | 0.0 | 0.0 | 1.0 mL | 1.0 mL | 8.0 mL | 2 | 1.0 mL | 10 | 1.0 mL | 1.0 mL | 7.0 mL | 3 | 3.0 mL | 30 | 1.0 mL | 1.0 mL | 5.0 mL | 4 | 5.0 mL | 50 | 1.0 mL | 1.0 mL | 3.0 mL | 5 | 7.0 mL | 70 | 1.0 mL | 1.0 mL | 1.0 mL | 6 | 2.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 6.0 mL | 7 | 4.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 4.0 mL | 8 | 6.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 2.0 mL |
The solutions were prepared as explained in the graph above. However, the lab did not provide us with sodium acetate, so 1.0 mL of water was substituted in its place. Test tube numbers 1-5 were created using a spectrophotometer 20 iron solution while the remaining test tubes, 6-8, were created using our unknown iron solution #12. The iron solution created for test tubes 6-8 was diluted twice. The first time, 1.0 mL of the unknown iron solution was pipetted into a 100 mL graduated cylinder. Distilled water was then added to it until the meniscus reached the 100 mL mark. For the second dilution, 25 mL of the first diluted solution was pipetted into another graduated cylinder and the same procedure was repeated. The spectrophotometer was plugged in and heated up for at least 15 minutes. The blank test tube (containing all components except iron solution) was then added to the spectrophotometer and set to 0 absorbance/100% transmittance. The absorbance of each solution was measured at 510 nm quickly after they were mixed. The table on the next page shows the absorbance of each test tube along with the micrograms of iron they contain.
Test Tube | Micrograms of iron | Absorbance (nm) | 1 | 0.0 (blank) | 0 nm | 2 | 10 | 0.20
By: Taylor Villari
Experiment conducted on 7/22/13
Components of each test tube examined in the spectrophotometer Trial | Volume of Iron solution (mL) | Micrograms of Iron | Volume of 10% sodium acetate | Volume of 0.1% o-phenanthroline | Volume of water (mL) | 1(blank) | 0.0 | 0.0 | 1.0 mL | 1.0 mL | 8.0 mL | 2 | 1.0 mL | 10 | 1.0 mL | 1.0 mL | 7.0 mL | 3 | 3.0 mL | 30 | 1.0 mL | 1.0 mL | 5.0 mL | 4 | 5.0 mL | 50 | 1.0 mL | 1.0 mL | 3.0 mL | 5 | 7.0 mL | 70 | 1.0 mL | 1.0 mL | 1.0 mL | 6 | 2.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 6.0 mL | 7 | 4.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 4.0 mL | 8 | 6.0 mL(unknown) | ? | 1.0 mL | 1.0 mL | 2.0 mL |
The solutions were prepared as explained in the graph above. However, the lab did not provide us with sodium acetate, so 1.0 mL of water was substituted in its place. Test tube numbers 1-5 were created using a spectrophotometer 20 iron solution while the remaining test tubes, 6-8, were created using our unknown iron solution #12. The iron solution created for test tubes 6-8 was diluted twice. The first time, 1.0 mL of the unknown iron solution was pipetted into a 100 mL graduated cylinder. Distilled water was then added to it until the meniscus reached the 100 mL mark. For the second dilution, 25 mL of the first diluted solution was pipetted into another graduated cylinder and the same procedure was repeated. The spectrophotometer was plugged in and heated up for at least 15 minutes. The blank test tube (containing all components except iron solution) was then added to the spectrophotometer and set to 0 absorbance/100% transmittance. The absorbance of each solution was measured at 510 nm quickly after they were mixed. The table on the next page shows the absorbance of each test tube along with the micrograms of iron they contain.
Test Tube | Micrograms of iron | Absorbance (nm) | 1 | 0.0 (blank) | 0 nm | 2 | 10 | 0.20