[ANALISIS PANGAN] - MATERI I - Kadar Besi Metode Spektrofotometri

Summary

This script describes the procedure for determining the concentration of a substance using spectrophotometry. First, a standard solution is prepared, and various volumes are tested in 100ml flasks with added reagents. The solution is then diluted and mixed thoroughly. The absorbance is measured using a spectrophotometer at a wavelength of 800 nm, first with a blank solution and then with the sample solution. Absorbance values are recorded, and the maximum and minimum absorbance are identified for further analysis, enabling accurate concentration determination of the sample.

Takeaways

• 😀 Prepare a standard FS100C m solution first for the experiment.
• 😀 Test the standard solution by taking different volumes (0.5, 1, 2, 3, 4, and 5 ml) and adding them to a 100 ml volumetric flask.
• 😀 Add 7 ml of H2S 28 and 15 ml of KSCN to the flask before diluting with distilled water to the mark.
• 😀 Homogenize the solution inside the volumetric flask to ensure proper mixing.
• 😀 Turn on the spectrophotometer and set the wavelength to 800 nm for absorbance readings.
• 😀 Insert a blank solution or phenol PPM into the cuvette and ensure the transparent side faces the light source.
• 😀 Set the blank on the spectrophotometer by pressing the setting blank button.
• 😀 Read the absorbance of the standard solutions at the set wavelength after blanking.
• 😀 Determine the maximum and minimum absorbance values for the standard solutions.
• 😀 Perform the same steps for the sample solution and read its absorbance at the same wavelength.

Q & A

What is the first step in determining the effect concentration in the procedure?

The first step is to prepare a standard solution, specifically the fs100c m solution.

How are the individual samples prepared for testing?

The standard solution is divided into separate volumes of 0.5, 1, 2, 3, 4, and 5 milliliters, which are then placed into 100 ml volumetric flasks.

What reagents are added to the volumetric flasks during the preparation?

7 milliliters of H2S 28 and 15 milliliters of KSCN are added to the volumetric flasks.

How is the solution made up to the required volume?

The solution is then diluted with aquadest (distilled water) up to the mark on the volumetric flask.

What is the next step after preparing the solution?

The solution is homogenized within the volumetric flask to ensure uniformity.

How should the spectrophotometer be set up for absorbance reading?

The spectrophotometer should be turned on and set to a wavelength of 800 nm.

What is done with the cuvette before measuring the absorbance?

The cuvette is filled with a blank solution or phenol PPM solution up to the triangular mark, ensuring the transparent side faces the light source inside the spectrophotometer.

What should be done after placing the blank solution in the cuvette?

After placing the blank solution in the cuvette, the 'Blank Setting' button on the spectrophotometer is pressed to calibrate it.

What is the procedure after setting the blank?

After setting the blank, absorbance readings are taken for all standard solutions.

What is the final step in the procedure?

The final step involves reading the absorbance of the sample solution at the same wavelength as the standard solutions and analyzing the results.