LAD B 1 Determination of Percentage of Copper

LAD B. 1 Determination of Percentage of Copper in a Brass Sample Using Spectrophotometry to determine concentration of an unknown solution. 1

Spectrophotometer schematic monochromator to narrow the beam of light to readout 2

Color as a function of wavelengths of Light Complementary Colors • Color in a visible spectrum and color wheel on your lab sheet. 3

Cobalt(II) nitrate Complementary Colors Co 2+ solution 4

Potassium permanganate Complementary Colors Mn. O 4− solution 5

Iron(II) chloride Complementary Colors Fe 2+ solution 6

Zinc nitrate Complementary Colors Zn 2+ solution 7

Potassium Chromate Complementary Colors 8

Copper(II) nitrate Complementary Colors Cu 2+ solution 9

Nickel(II) chloride Complementary Colors Ni 2+ solution 10

Handling cuvettes • Please be careful and do NOT place your fingers on the clear sides. • Handle only the ridged sides 11

Reminder of how to use the pipet pumps/bulbs 12

Spectrophotometer change between absorbance and transmittance readout sample compartment on/off and zero knob adjust to zero with no cuvette − do not adjust again Adjust wavelength 100 % transmittance adjust to 100% transmittance with cuvette and deionized water 13

Vernier Spectro. Vis How to Use the Vernier Spectro. Vis 14