I am having problems on some homework, and was wondering if anyone could help me figure out how to do either of the two questions.....


a.)Chromatographic peaks ideally have a Gaussian peak shape; therefore, a Table of areas under the normal distribution curve can be used to give the theoretical area when integrating a peak over the x-variable, which is usually time. If a chromatographic peak, which has a standard deviation of sigma, elutes with retention time, tr, then what percentage of the peak lies to the right of tr + 1.4sigma ?


b.)If a solid sample contains about 125 ppm of Ca, how many mg of sample must be dissolved in 100-mL in order to give a solution that is about 1 ppm after dilution? answer is left in mg of sample

Thank you

6/3/2006 6:44:44 PM