In

this experiment, the most common problem in analytical chemistry was faced: determining

the quantity of an unknown compound in a given sample. This can be solved by

using instrumental analysis with the only issue remaining being the composition

of the unknown itself and whether or not reminisce of concomitants will shift

the results collected.

The simplest way to determine the

mass of the unknown compound is to create a calibration curve by using known

standards of the desired unknown compound and conclude the mass of the unknown

compound depending on where on the curve the signals falls. In this case,

standard solutions of riboflavin are prepared (x-value) and their recorded

signals (y-value) were respectively plotted which will give a linear

regression-line following the equation:

(Equation 1)

where

y is the signal obtained, m is the slope of the line, x is the concentration of

the known compound (riboflavin) and b being the y-intercept of the line. The

concentration of the desired analyte in the unknown compound can be calculated

by plugging in the signal obtained for the y-value and solve for x. A

disadvantage of this method is that the concentration of the unknown mass has

to fall within the linear dynamic range of the standard solutions prepared.

Linear dynamic range is defined as the range of data points where the output

has a linear function to the input. The limited of this range can be defined as

the linear line, these curve tend to deviate and from plateaus with increasing

inputs.

Multiple standard addition resolves

the same problem as a calibration curve by using the spiking of the desired

sample.