Final Remarks - Lesson 3 - Some Special Topics: Reactions in Solutions - Liquid-State Physical Chemistry: Fundamentals, Modeling, and Applications (2013)

Liquid-State Physical Chemistry: Fundamentals, Modeling, and Applications (2013)

14. Some Special Topics: Reactions in Solutions

14.8. Final Remarks

In this chapter, following an introduction to TST, we discussed the relevance of reaction- and diffusion-limited reactions. Moreover, the influence of dipole moment, permittivity and ionic strength of the solvent was treated. It is clear that trends can be predicted reasonably well, but that precise estimates cannot be expected.

Notes

1) Participation of a solvent in a reaction is not easily discerned since its molarity changes very little. Also participation of a catalyst is cumbersome since after reaction its concentration is unchanged.

2) This argument is based on the existence of order, as defined by Eq. (14.5), but the result is generally valid.

3) Alternatively, we consider the reaction coordinate as the coordinate for which ω → 0. In that limit the vibrational contribution to the partition function reads kT/ħω. For an ordinary vibration of a bond, the circular frequency ωwould be the reciprocal of the time τ to make a complete vibration; that is, traversing the length δ twice. Here, we need the frequency for traversing δ only once, that is, 2ω. Hence, the rate r = ½[(ABC)] 2ω, leading to the same final result.

References

1 See Laidler (1987).

2 See Connors (1990).

3 See Arnaut et al. (2007).

4 This approximation can be rationalized, see, e.g., (a) Bernasconi, C.F. (ed.) (1986) Investigation of Rates and Mechanisms of Reactions, Part 1, John Wiley & Sons, New York; (b) Steinfeld, J.I., Francisco, J.S., and Hase, W.L. (1998) Chemical Kinetics and Dynamics, 2nd edn, Prentice-Hall.

5 (a) Raff, L.M. (2001) Principles of Physical Chemistry, Prentice-Hall, Upper Saddle River, NJ; (b) Levine, I.N. (2002) Physical Chemistry, 5th edn, McGraw-Hill, Boston; (c) Kirkwood, J.G. (1934), J. Chem. Phys., 2, 351.

6 Benesi, A.J. (1982) J. Phys. Chem., 86, 4926.

7 Lyon, R.K. and Levy, D.H. (1961) J. Am. Chem. Soc., 83, 4290.

8 See Buncel et al. (2003).

9 See Reichardt (2003).

10 Kirkwood, J.G. (1934) J. Chem. Phys., 2, 351.

11 See Glasstone et al. (1941).

Further Reading

Arnaut, L., Formosinho, S., and Burrows, H. (2007) Chemical Kinetics, Elsevier, Amsterdam.

Buncel, E., Stairs, R., and Wilson, H. (2003) The Role of Solvents in Chemical Reactions, Oxford University Press, Oxford.

Connors, K.A. (1990) Chemical Kinetics, Wiley-VCH Verlag GmbH, Weinheim, Germany.

Glasstone, S., Laidler, K.J., and Eyring, H. (1941) The Theory of Rate Processes, McGraw-Hill, New York.

Laidler, K.J. (1987) Chemical Kinetics, 3rd edn, Harper and Row, London.

Moore, J.W. and Pearson, R.G. (1981) Kinetics and Mechanism, 3rd edn, John Wiley & Sons, Inc., New York.

Reichardt, R. (2003) Solvents and Solvent Effects in Organic Chemistry, 3rd edn, Wiley-VCH Verlag GmbH, Weinheim, Germany; See also 2nd edn (1988), Wiley-VCH, Weinheim, Germany.

Soustelle, M. (2011) An Introduction to Chemical Kinetics, John Wiley & Sons, Ltd, Chichester.

Wright, M.R. (2004) Introduction to Chemical Kinetics, John Wiley & Sons, Ltd, Chichester.