You can read more about standard additions here.
https://en.wikipedia.org/wiki/Standard_addition
y = mx + b is straight line.
m is slope = 0.103
b is the intercept = 0.135 and that will be - if the x intercept.
Then solve for x = concentration in ppm. It is unclear in the problem if the unit of ppm concn is in the diluted or undiluted sample; i.e. you may need to correct the initial sample.That is you have diluted it from 25 mL to 100 mL so the final concentration may be 4x that (that's 100 mL/25 mL).
A student does a standard addition experiment by pipetting 25 mL of unknown, adding ferrous ion spikes and reagents, into a 100 mL volumetric flask and making up to the mark. The equation of the line has a slope of 0.103 and an intercept of 0.135 when the unit of concentration was in ppm. What is the concentration of Fe(II) in the unknown?
1 answer
1 answer