- Question Completion Status 7 8 10 Choose As Many As Apply Using A Freshly Cleaned Cuvette For Each Reading On The Spec 1 (72.31 KiB) Viewed 69 times
Remaining Question Completion Status: 5 6 8 7 3 10 2 9 14 1.6 0.4 0.6 03 1 1.2 Concentration wg/ul However there are limitations to using a spectrophotometer for measuring color. The linear range is usually from 0.2 to 0.8 absorbance units (200 to 800 in the graph above). Higher than 0.80 a.u. the curve saturates off and the reading is no longer reliable, and below th 0.20 a.u. the linearity/sensitivity is unreliable. This saturation effect often requires the experimenter to perform several preliminary tests to ascertain the experimental conditions to stay within that linear range, such as (1) best absorption wavelength, (2) concentration (molarity) of colored compound to b used, and (3) the reaction time needed for color development. == What are the necessary considerations when constructing a CONTROL curve for the intended experiment. Choose as many as apply.
7 5 8 10 2 (5 points) When performing an experiment that generates a colored product (in our case a blu food dye), we often use a spectrophotometer to measure the intensity of color absorption as marker for the reaction under study. The theory behind this approach is called Beer's Law and it is represented by the following equation: Beer's Law: A=&bc Absorbance = (€ - molar absorptivity coefficient) x (b - light path length (usually 1.0 centimeters) through the cuvette) x (c — molarity of the measured substance) Non-Linear regression 2000 1600 100 R=09906 300 000 400 200