CHEM 209 Quiz 3 Latest Version with Complete Solutions

CHEM 209 Quiz 3 Latest Version with Complete Solutions What variables are typically plotted on the x- and y-axes of a chromatogram? x-axis: time, y-axis: response What variables are typically plotted on the x- and y-axes of a calibration curve? x-axis: concentration, y-axis: peak area What term describes the time it takes for a molecule to move through the column? retention time What term describes the material coating the inside of the column in chromatography? stationary phase What is the term for the ratio of molar concentration of analyte in the stationary phase to that in the mobile phase? partition coefficient 2 What is another term for the mobile phase in chromatography? carrier gas Typically, will an increase in operating temperature or mobile phase flow rate result in longer or shorter retention times for chromatographic peaks? shorter Why does an increase in operating temperature or mobile phase flow rate generally lead to shorter retention times for chromatographic peaks? Faster flow through the column If you need to decrease the retention times of peaks in a chromatogram, what are three specific GC conditions you could modify? oven temperature, mobile phase flow rate, column length In a GC experiment, a student injects 2.0 μL of a 20% ethanol/water solution. Calculate the weight of ethanol injected. (Ethanol density: 0.789 g/mL at 20°C) 0.3156 mg