A student researcher performed a chromatographic separation of caffeine and aspartame. The retention time for caffeine, tc, was found to be 207.9 s with a baseline peak width, wc, of 13.9 s and the retention time for aspartame, ta, was 264.2 s with a baseline peak width, wa, of 22.2 s. The retention time for the unretained solvent methanol was 47.0 s. Calculate the average plate height in micrometers for this separation, given that it was performed on a 16.8-cm long column.

What happens when chlorine reacts with bromine? a. electrons move from the chlorine atoms to the bromine atoms. b. electrons move from the bromine atoms to the chlorine atoms. c. electrons are shared between the chlorine atoms and the bromine atoms. d. electrons become delocalized among the atoms.

Thomas his older brothers, who own a junk yard, on the weekends to earn extra money. he likes to them push broken-down cars to the back of the junk yard because it makes him feel strong. last saturday, they pushed three cars with different weights, and he noticed he used different amounts of force for each one. the cars were the following weights: white car: 2,700 kg red car: 1,500 kg blue car: 2,100 kg think about how much force is needed to move each car. which correctly lists the cars in order from the most to least amount of force needed to move them? a) white, blue, red b) blue, red, white c) red, white, blue d) white, red, blue

Which of these is constant for all types of electromagnetic radiation in a vacuum? select one: a. wavelength b. frequency c. photon energy d. amplitude e. velocity