A photometer with a linear response to radiation gave a reading of 529 mV with the solvent in the light path and 272 mV when the solvent was replaced by an absorbing solution. The photometer was set to zero with no light striking the detector. Calculate: a. the percent transmittance and absorbance of the absorbing solution.
b. the expected transmittance if the concentration of absorber is one half that of the original solution.
c. the transmittance to be expected if the light path through the original solution is doubled.

The two naturally occurring isotopes of chlorine are 35cl (34.969 amu, 75.77%) and 37cl (36.966 amu, 24.23%). the two naturally occurring isotopes of bromine are 79br (78.918 rm amu, 50.69%) and 81br (80.916 amu, 49.31%). chlorine and bromine combine to form bromine monochloride, brcl. 1. how many peaks will be present in a mass spectrum for brcl? the four combinations of molecule possible given these four isotopes are: 81br37cl, 81br35cl, 79br37cl, and 79br35cl. 2. what are the masses of the four different brcl molecules? express the masses using six significant figures, in decreasing numeric order (highest to lowest), separated by commas.