GENERAL CHEMISTRY(LL)-W/MASTERINGCHEM.
11th Edition
ISBN: 9780134566030
Author: Petrucci
Publisher: PEARSON
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Chapter 11, Problem 68IAE
A conjugated hydrocarbon has an alternation of double and single bonds. Draw the molecular orbitals of the p system of 1,3,5- hexatriene. If the energy required to excite an electron from the HOMO to the LUMO corresponds to a wavelength of 256 nm, do you expect the wavelength for
the corresponding excitation in 1,3,5,7-octatetraene to be a longer or shorter wavelength? [Hint: Refer to Figure 11-34.]
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6) This question is concerned with vibrational spectra (Infrared and Raman).
a) How many normal modes of vibration are expected in these molecules? (Show calculations)
i) Theobromine (the caffeine-like stimulant that is found in chocolate)
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(arrows). Will this mode be IR active?
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In each case, why or why not?
ii) Cyanopolyyne (an organic molecular wire that has been detected spectroscopically in interstellar space, and
is postulated to be a precursor to biomolecules: HC=C-C=C-C=N
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KB/s
1. The C-C stretch in allene (H,C-C=CH,) is about 1650 cm'; the C-H stretch is about
3,100 cm". Calculate the corresponding wavelengths (in nm) and energies (in
kJ/mol) of these vibrations.
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II
This question pertains to the heteronuclear diatomic 1H19
Given that the bond length of 1H19F is 0.91 angstrom (1 angstrom = 10-10m), calculate the moment of inertia.
Calculate the rotational constant (in J) for the diatomic in part a.
Using your value for the rotational constant in part b, determine the energy of the transition from state 3 to state 4 (in J).
Do you expect the energy of the transition from state 3 to state 4 for 2H19F to be larger or smaller than what you computed in part c, assuming that the bond length does not change? Explain your choice based on the relevant equations, or calculate the energy for this transition.
Steps 1, 2 and 3 have already been found. I need help with the last question only but I haven't been able to get it solved since there can only be three questions answered. The following answers for step 1-3 are below.
1. moment of inertia = 1.30 × 10-47 kgm2
2. rotational constant = 21.5 cm-1
3. Energy required from transition n= 3 to n= 4 is…
Chapter 11 Solutions
GENERAL CHEMISTRY(LL)-W/MASTERINGCHEM.
Ch. 11 - Prob. 1ECh. 11 - Explain why it is necessary to hybridize atomic...Ch. 11 - Describe the molecular geometry of H2O suggested...Ch. 11 - Describe the molecular geometry of NH2 suggested...Ch. 11 - In which of the following, CO32-,SO2,CCl4,CO,NO3-...Ch. 11 - In the manner of Example 11-1, describe the...Ch. 11 - For each of the following species, identify the...Ch. 11 - Propose a plausible Lewis structure, geometric...Ch. 11 - Describe a hybridization scheme for the central Cl...Ch. 11 - Describe a hybridization scheme for the central S...
Ch. 11 - Match each of the following species with one of...Ch. 11 - Propose a hybridization scheme to account for...Ch. 11 - Indicate which of the following molecules and ions...Ch. 11 - In the manner of Figure 11-18, indicate the...Ch. 11 - Write Lewis structures for the following...Ch. 11 - Represent bonding in the carbon dioxide molecule,...Ch. 11 - Use the method of Figure 11-19 to represent...Ch. 11 - Use the method of Figure 11-19 to represent...Ch. 11 - The molecular model below represents citric acid,...Ch. 11 - Malic is e common organic acid found in unripe...Ch. 11 - Shown below are ball-and-stick models. Describe...Ch. 11 - Shown below are ban-and-stick models. Describe...Ch. 11 - Prob. 23ECh. 11 - The structure of the molecule allene, CH2CCH2 , is...Ch. 11 - Angelic acid, shown below, occurs in symbol root,...Ch. 11 - Dimethylolpropionic acid, shown below, is used in...Ch. 11 - Explain the essential difference in how the...Ch. 11 - Describe the bond order of diatomic carbon, C2 ,...Ch. 11 - Prob. 29ECh. 11 - The paramagnetism of gaseous B2 has been...Ch. 11 - Prob. 31ECh. 11 - Is it correct to say that when a diatomic molecule...Ch. 11 - For the following pairs of molecular orbitals,...Ch. 11 - For each of the species C2+,O2,F2+ , and NO+ ; a....Ch. 11 - Write plausible molecular orbital occupancy...Ch. 11 - We have used the term “isoelectronic” to refer to...Ch. 11 - Consider the molecules NO+ and N2+ and use...Ch. 11 - Consider the molecules CO+ and CN- and use...Ch. 11 - Construct the molecular orbital diagram for CF....Ch. 11 - Construct the molecular orbital diagram for SrCl....Ch. 11 - Explain why the concept of delocalized molecular...Ch. 11 - Explain how it is possible to avoid the concept of...Ch. 11 - In which of the following molecules would you...Ch. 11 - In which of the following ions would you expect to...Ch. 11 - The Lewis structure of N2 indicates that the...Ch. 11 - Show that both the valence bond method and...Ch. 11 - A group of spectroscopists believe that they have...Ch. 11 - Lewis theory is satisfactory to explain bonding in...Ch. 11 - The compound potassium sesquoxide has the...Ch. 11 - Draw a Lewis structure for the urea molecule, CO(...Ch. 11 - Methyl nitrate, CH2NO2 , is used as a rocket...Ch. 11 - Fluorine nitrate, FONO2 , is an oxidizing agent...Ch. 11 - Draw a Lewis structure(s) for the nitrite ion, NO2...Ch. 11 - Think of the reaction shown here as involving the...Ch. 11 - Prob. 55IAECh. 11 - Prob. 56IAECh. 11 - The molecule formamide, HCONH2 , has the...Ch. 11 - Pyridine, C2H2N , is used in the synthesis of...Ch. 11 - Prob. 59IAECh. 11 - The ion F2Cl is linear, but the ion F2Cl+ is bent....Ch. 11 - Prob. 61IAECh. 11 - Prob. 62IAECh. 11 - Prob. 63IAECh. 11 - Prob. 64IAECh. 11 - Histidine, an essential amino acid, serves as a...Ch. 11 - The anion I42 is linear, and the anion I5 is...Ch. 11 - Prob. 67IAECh. 11 - A conjugated hydrocarbon has an alternation of...Ch. 11 - An elusive intermediate of atmospheric reactions...Ch. 11 - Resonance energy is the difference in energy...Ch. 11 - Furan, C4H4O , is a substance derivable from oat...Ch. 11 - As discussed in Are You Wondering 11-1, the sp...Ch. 11 - In Chapter 10, we saw that electronegativity...Ch. 11 - Borazine, B2N2H2 is often referred to as inorganic...Ch. 11 - Which of the following combinations of orbitals...Ch. 11 - Prob. 76FPCh. 11 - Prob. 77SAECh. 11 - Prob. 78SAECh. 11 - Explain the important distinctions between the...Ch. 11 - A molecule in which sp2 hybrid orbitals are used...Ch. 11 - Prob. 81SAECh. 11 - The hybridization scheme for the central atom...Ch. 11 - Of the following, the species with a bond order of...Ch. 11 - The hybridization scheme for Xe in XeF2 is (a) sp;...Ch. 11 - Delocalized molecular orbitals are found in (a)...Ch. 11 - Prob. 86SAECh. 11 - Why does the hybridization sp2d not account for...Ch. 11 - What is the total number of (a) bonds and (b) p...Ch. 11 - Which of the following species are paramagnetic?...Ch. 11 - Use the valence molecular orbital configuration to...Ch. 11 - Use the valence molecular orbital configuration to...Ch. 11 - Which of these diatomic molecules do you think has...Ch. 11 - For each of the following ions or molecules,...Ch. 11 - Draw Lewis structures for the NO2 and NO2+ ions,...Ch. 11 - In which of the following is the central atom sp...Ch. 11 - Prob. 96SAECh. 11 - According to molecular orbital theory, the O22 ion...Ch. 11 - What is the angle between the hybrid orbitals...Ch. 11 - Consider the molecule with the Lewis structure...Ch. 11 - Construct a concept map that embodies the ideas of...Ch. 11 - Prob. 101SAECh. 11 - Construct a concept map that describes the...
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