In:
Canadian Journal of Chemistry, Canadian Science Publishing, Vol. 53, No. 3 ( 1975-02-01), p. 427-436
Abstract:
Raman spectroscopy has been employed to follow the relatively slow rate of hydrolysis of acetonitrile, catalyzed by mercury(II). Raman lines at 2275 and 2305 cm −1 are characteristic of CH 3 CN bound to Hg 2+ , and are distinct from lines of bulk solvent. The intensities of these new lines decrease with time. From the intensities, concentrations of bound acetonitrile, [CH 3 CN] B were calculated for a time span of 400 min. The data fit a second order rate law: Rate = k[CH 3 CN] B [H 2 O]. The specific rate constant, k, obtained from four sets of data for the system Hg(ClO 4 ) 2 –CH 3 CN–H 2 O equals 1.05 ± 0.06 × 10 −4 mol −1 1 min −1 at 25 °C. The energy of activation is 18.9 kcal mol −1 . In the proposed mechanism water molecules attack acetonitrile molecules which are bound to Hg 2+ and form a mercury(II)–acetamide complex. Raman lines characteristic of this species are observed. This species slowly converts to mercury(II) ammine complexes and acetic acid. Anions which coordinate with Hg 2+ more strongly than CH 3 CN, such as nitrate or acetate, slow or prevent the hydrolysis reaction.
Type of Medium:
Online Resource
ISSN:
0008-4042
,
1480-3291
Language:
English
Publisher:
Canadian Science Publishing
Publication Date:
1975
detail.hit.zdb_id:
1482256-8
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