Electron spin magnetic moment and energy levels that occur in the presence of an external magnetic field.

Complete the following table. Which nucleus requires the least energy to flip its spin at this applied field? Which nucleus requires the most energy? Applied Field (tesla, T) Radio Frequency (MHz) Nucleus Energy (J/mol) 7.05 300 13C 7.05 75.5 19F 7.05 282

the shielding in NMR is: a) Place a metal around the sample tube before staining it on the instrument.b) use a metal block to avoid being attacked by an opponentc) blocking the view of a participant in a concertd) when the magnetic moment of an atom blocks the induced magnetic moment of neighboring nuclei

If a sample is placed in a magnetic field of applied field strength = 1.1 Tesla, the spin-up and spin-down 1H nuclei show an energy difference that corresponds to a photon with frequency = 60 MHz.  If this same sample is moved into the vicinity of a magnetic field of strength = 5.5 Tesla, what will be the frequency of a photon that could match the energy difference of the spin-up and spin-down states?

Which of the following transitions will require the longest wavelength of an electromagnetic radiation? Electronic excitation from the ground state to the first excited state Electronic excitation from the third excited state to the fourth excited state Electronic excitation from the first excited state to the second excited state Electronic excitation from the fourth excited state to the fifth excited state Electronic excitation from the second excited state to the third excited state

Spectroscopy relies on the excitation and relaxation of electrons. Which of the following statements about spectroscopy is true? Phosphorescence is the emission of a photon of light as an electron transitions from the excited singlet state to ground state. Collisional deactivation of an excited molecule decreases the absorbance response. Molecular absorption spectrometry measures the change in light intensity as light passes through a sample. Fluorescence is the absorption of a photon of light as an electron transitions from the ground state to an excited triplet state.

Using photoelectron spectroscopy, the ionization energy of the least tightly bound valence electron on Cl was determined to be 13.0 eV. Calculate the Zeffective for this electron.

2. a. Copper(II) acetate is a dimer, and the two copper atoms are strongly interacting. The epr spectrum consists of seven lines with intensity ratios 1:2:3:4:3:2:1. Copper nuclei have an I value of 2, and copper acetate consists of a ground state that is a singlet and an excited state that is a triplet. Explain the number and relative intensity of the lines in the spectrum. [For answer, see B. Bleaney and K. D. Bowers, Proc. Roy. Soc. (London), A214, 451 (1952).] b. What would you expect to happen to the signal intensity as a sample of copper acetate is cooled? Why?

Beta-carotene is an organic compound with an orange color. The diagram above shows the ultraviolet spectrum of beta-carotene. Which of the following statements is true about the absorption bands in the spectrum?(see attached image) a.) The absorption band between 250250 and 320 nm320 ⁢⁢nm is due to transitions in electronic energy levels, and the absorption band between 380 and 520 nm is due to transitions in molecular vibrational levels.   b.) The absorption band between 250 and 320 nm is due to transitions in molecular vibrational levels, and the absorption band between 380 and 520 nm is due to transitions in molecular rotational levels.   c.) The two main absorption bands are associated with transitions in electronic energy levels. The band in the region corresponding to shorter wavelengths shows a lower absorbance than the band in the region corresponding to longer wavelengths. d.) The two main absorption bands are associated with transitions in molecular vibrational levels.…

Which of the following is the function of the Flame or Emission system in Atomic Absorption Spectroscopy? Choose the best answer.      To heat the sample      To break the atoms by heating     To split the atoms into particles         To reduce the sample into atomic vapor state