A peak elutes from an HPLC column 13.3 cm in length in 15.3 min. What would be the width at half-height of the peak (in seconds) if the plate height were 8.62 µm? w1/2 = What would be the width at half-height of the peak (in seconds) if the plate height were 43.0 µm? W12 =

A peak elutes from an HPLC column 17.4 cm in length in 11.4 min. What would be the width at half-height of the peak (in seconds) if the plate height were 4.66 µm? W1/2 What would be the width at half-height of the peak (in seconds) if the plate height were 42.0 µm? W 1/2 = S S

A photon of light has a wavelength of 1967 nm. Calculate the energy for 1 photon of light. h = 6.626 x 10-34 J*s, c = 3.00 x 10° m/s, Na = 6.02 x 1023 %3D 1.525 x 1014, 60,840 J 1.011 x 10-34, 1.011 x 10-19,

An unknown sample of Mn2+ gave an absorbance of 0.392 in an atomic absorption analysis.  Then 2.00 mL of solution containing 100.0 ppm of Mn2+ (=μg/mL) was mixed with 90.0 mL of unknown, and the mixture was diluted to 100.0 mL in a volumetric flask.  The absorbance of the new solution was 0.600.  The blank reading for this experiment is 0.010.   Denoting the initial, unknown concentration as [Mn2+]i, write an expression for the final concentration, [Mn2+]f, after dilution.  Units of the concentration are ppm.   In a similar manner, write the final concentration of added standard Mn2+, designated as [S]f.   Find [Mn2+]i in the unknown.