D.D. Nelson et al. (Science 238, 1670 (1987)) examined several weakly bound gas-phase complexes of ammonia in search of examples in which the H atoms in NH3 formed hydrogen bonds, but found none. For example, they found that the complex of NH3 and CO2 has the carbon atom nearest the nitrogen (299 pm away): the CO2 molecule is at right angles to the C–N ‘bond’, and the H atoms of NH3 are pointing away from the CO2. The magnitude of the permanent dipole moment of this complex is reported as 1.77 D. If the N and C atoms are the centres of the negative and positive charge distributions, respectively, what is the magnitude of those partial charges (as multiples of e)?

D.D. Nelson et al. (Science 238, 1670 (1987)) examined several weakly bound gas-phase complexes of ammonia in search of examples in which the H atoms in NH3 formed hydrogen bonds, but found none. For example, they found that the complex of NH3 and CO2 has the carbon atom nearest the nitrogen (299 pm away): the CO2 molecule is at right angles to the C–N ‘bond’, and the H atoms of NH3 are pointing away from the CO2. The magnitude of the permanent dipole moment of this complex is reported as 1.77 D. If the N and C atoms are the centres of the negative and positive charge distributions, respectively, what is the magnitude of those partial charges (as multiples of e)?

Physical Chemistry

2nd Edition

ISBN:9781133958437

Author:Ball, David W. (david Warren), BAER, Tomas

Publisher:Ball, David W. (david Warren), BAER, Tomas

Chapter14: Rotational And Vibrational Spectroscopy

Section: Chapter Questions

Problem 14.85E

See similar textbooks

Similar questions

15. Modeling ligand binding. A ligand is bound to a protein with a spring-like square-law energy e(x), where x is the distance between the ligand and protein as shown in the figure. e(2) = }ca² Protein Ligand (a) For constant (T,V,N), write an expression for the probability distribution p(x) of the ligand separation from the protein. (b) Sketch a plot of p(x) vs x. Write an expression for the average location of the ligand, (x). (d) Write an expression for the second moment of the location of the ligand, (x2). (e) Calculate the average energy, (e) of the system.
A complex of formula [M(N ≡ CCH3)6](NO3)2, in which the M(II) ion is that of a firstrow (3d) transition metal, has a magnetic moment of μeff = 2.83 B.M What is the possible identity of the M(II) ion?
(b) The formula that relates the spin only magnetic moment (en) to the number of unpaired d-electrons (x) is: Heft = √√x(x+2) (1) For each of the following complexes, use this formula to calculate the number of unpaired electrons: Nan[Rh(CO)4], Hell0 BM Rb₂lMoBrn), Heft=2.83 BM (ii) Using the answers from part (b)(i): • Draw crystal field d-orbital energy level diagrams for each complex. • State the oxidation state of the metal in each complex. • Determine the value of n for each complex.
Tungsten hexacarbonyl (W(CO)6) is reacted with (EtC≡N) and the product is W(CO)3(N≡CEt)3.However, the product can be a mixture of fac and mer isomers. But a Chemist can determine fromanalysis of the infrared spectrum if the product is indeed a mixture of isomers or not. In thesynthesis experiment, the product shows 3 carbonyl stretching frequencies in the infraredspectrum, at 2021, 1898 and 1840 cm-1. Determine the irreducible representations of the stretchesexpected for each of the two species in their respective point group. Can you confirm what isomerwas isolated?
The molecu le 2,2'-bipyridine (1, bpy) forms a complex with the Ru2+ ion. Ruthenium(ll) tris-(2,2'-bipyridyl), Ru(bpy)3,2+(2), has a strong electronic absorpt ion at 450 nm . The quenching of the * Ru(bpy)3 2+ excited state by Fe(OH2)63+. in acidic solution was monitored by measuring excited state lifetimes at 600 nm. Determine the quenching rate constant for this reaction from the following data:
(i) Determine the IR and Raman active modes of vibrations for both the cis and trans isomers of L2M(CO)4,
The molecule with simple formula N2F2 has several isomers; two of these isomers have central nitrogens, with a terminal fluorine on each nitrogen. Show the Lewis Dot Diagram. For the cis isomer : What is the point group? (include formal charges, if any). Write also the main symmetry elements How many IR bands bands would you expect if vib = 3A1 + A2 +2B2? For the trans isomer : What is the point group? (include formal charges, if any). Write also the main symmetry elements How many IR bands bands would you expect if vib = 3Ag + Au +2Bu?
The oxidation of HSO3− by O2 in an aqueous solution is a reaction of importance to the processes of acid rain formation and flue gas desulfurization. R.E. Connick et al. (Inorg. Chem. 34, 4543 (1995)) report that the reaction 2 HSO3−(aq) + O2(g) → 2 SO42−(aq) + 2 H+(aq) follows the rate law v = kr[HSO3−]2[O2]2. Given pH = 5.6 and an O2 molar concentration of 0.24 mmol dm−3 (both presumed constant), an initial HSO3− molar concentration of 50 μmol dm−3, and a rate constant of 3.6 × 106 dm9 mol−3 s−1, what is the initial rate of reaction? How long would it take for HSO3− to reach half its initial concentration?
P18C.7 The study of conditions that optimize the association of proteins in solution guides the design of protocols for formation of large crystals that are amenable to analysis by X-ray diffraction techniques. It is important to characterize protein dimerization because the process is considered to be the rate-determining step in the growth of crystals of many proteins. Consider the variation with ionic strength of the rate constant at 298 K of dimerization in aqueous solution of a cationic protein P: I 0.0100 0.0150 0.0200 0.0250 0.0300 0.0350 8.10 13.30 20.50 27.80 38.10 52.00 What can be deduced about the charge of P?
True or false and why is false 1 There are 2 major classes of keratins: alpha keratins (found in mammals) and beta keratins (found in feathers and scales of birds and reptiles) 2 One estimate of mobility within a crystal is the B-factor that reflects spreading or blurring of electron density 3 In NMR, the longitudinal relaxation time (T1) reflects the rate at which magnetization returns to the longitudinal axis after a pulse
Determine the final concentration in mol dm–3 of K+ and SO42– when the following three solutions in volumetric flasks are mixed together: 500 cm3 of 0.20 mol dm–3 KAl(SO4) 2; 1000 cm3 of 0.050 mol dm–3 K2SO4 and 500 cm3 of water. The concentration of K+ is Select one: a. 0.20 × 103 mol dm–3 b. 0.20 mol dm–3 c. 0.10 × 10–3 mol dm–3 d. 0.10 mol dm–3
Given the fact that O2, N2, and O in the upper atmosphere absorb most of the light with wavelengths shorter than 240 nm, would you expect thephotodissociation of C ¬ F bonds to be significant in the lower atmosphere?