# STATS/CHEM

posted by
**Ashley** on
.

I get how to use the method of least squares to determine slope, intercept, uncertainties in slope and intercept of your graph and but am confused how to determine the error of mole percent stated in (ii)

The following are peak areas for chromatograms of isooctane standards

Peak area Mole percent isotane

0.352 1.09

0.803 1.78

1.08 2.60

1.38 3.03

1.75 4.01

(i)Use the method of least squares to find the slope, intercept, uncertainties in slope and intercept of your graph and give the equation of the line.

(ii) A peak area of 2.65 was obtained for an unknown sample of hydrocarbon mixture. Calculate the mole percent of isooctane in the mixture, error of the mole percent and the 95% confidence interval of the mole percent if the peak area was

(a) the result of a single measurement and

(b) the mean of four measurements

(c) comment on the difference in answers to (a) and (b)

Hope anyone can help me with this homework