If chlorophyll had absorption peaks at 550 nm and 650 nm rather than 425 nm and 660 nm what colour would the leaf appear to your eyes?

d. Which of the following is the structural formula for phenacetin, which is synthesized by treating 4- ethoxyaniline with acetic anhydride? CH3CH₂O- CH3CH₂O- HII -N-C-CH3 H -N-O-C-CH3

What is the difference with UV single beam vs double beam and how does it affect absorbance?

Why are n-π* transitions generally of low intensities/low absorptions?

The 13C NMR spectrum of fluoroethanoic acid shows a multiplet centred at δ = 79. When the same spectrum is recorded using proton decoupling, the multiplet collapses to a doublet with a splitting of 160 Hz. Another multiplet, but with much smaller splittings, is also seen centred at δ =179; this multiplet collapses to a doublet when decoupling is used. Explain these observations.

(c) Aqueous solutions of Co2+ salts are pale pink. They contain the complex ion [Co(H₂O)]2+. Addition of concentrated HCl results in a profound colour change to dark blue, due to formation of [CoC14]. The main absorption bands of [Co(H₂O)6]2+ and [CoC14] occur at 19400 cm¹ (~10 M¹ cm') and 14700 cm¹ (~ 1000 M¹ cm¹), respectively. (i) Explain the difference in the transition energies between the two complexes. (ii) Explain why the absorption band of [CoC14]² is much more intense than that of [Co(H2O)%]2+. (d) Calculate the ligand field stabilisation energy of the following complexes: (i) [Mn(H₂O)6]2+ (ii) [Fe(CN)6]³ (iii) [CoC14]²-

In infrared spectra, the O-H vibrational frequency of alcohols occurs as a broad peak (peak absorbable) in the region 3200-3600 cm -1, true or false?

5. n5° of dichloromethane is 1.4244. If a 0.97 g sample of pure dichloromethane was contaminated with 1 drop of ethanol, what do you think the effect would be on the refractive index and by approximately how much? (1 drop of ethanol weighs about 0.03 g).

2. The rovibrational absorption spectrum below corresponds to the V4 band of NH3. Use the wavenumbers of the visible lines in the zoomed region to determine the distance (in Å) of the hydrogen atoms from the principal (C3) axis. Note the lines are colour coded for AK. mN = 14.007 amu, m₁ = 1.008 amu. Q -R 1400 1500 1600 1700 1800 V/cm-1 AK = 0 AK = ±1 1623.75- 1627.00- 1630.25- 1636.44- 1642.64- 1649.14- 1645.89 1655.03- 1661.52- 1664.78- v/cm-1

Use group theory to predict the number of v(CO) stretching vibrations you would expect to observe in the IR and Raman spectra of cis and trans isomers of Mo(CO)4(PPh3)2. Can these isomers be differentiated by vibrational spectroscopy?   (ii) Can these isomers be differentiated by 31P{H} and 13C {¹H} spectroscopy? Fully explain your answer in both cases explaining what you would expect to see in each spectrum.   (iii) Reaction of both isomers with more PPh3 affords mixtures of fac and mer isomers of [Mo(CO)3 (PPh3)3]. Give the point groups for each. Can they be distinguished by IR spectroscopy?   Please give me all answers