Vibrational degrees of freedom Nonlinear molecule 3 N 3 3 3 N 6 Linear molecule

# Vibrational degrees of freedom nonlinear molecule 3 n

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Number of Degrees of Freedom How many rotational and vibrational degrees of freedom do the following molecules have? O 2 4 3
Experimental Methods in Molecular Spectroscopy Absorption spectra can be recorded with a spectrophotometer. Measure transmittance T = I S / I R or absorbance A = ln[ I R / I S ] vs. λ . Relate to molecular properties: –ln I S / I R = –ln T = A = a , where is the cell length. Parameter a is the absorption , or extinction , coefficient (units: length –1 ) NOTE: In Intro Chem Lab, A defined as log 10 [ I R / I S ]. Values will differ by factor of ln(10) = 2.303. Log 10 is used in solution manual.
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Problem The percent transmission at 250 nm through a certain aqueous solution is 20%. The cell length is 1.0 cm, and the solution concentration is 510–4mol L–1. Calculate the molar absorption coefficient.
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