Kinetics of Oxygen Exchange between the Two Isomers of Bisulfite Ion, Disulfite Ion (S<sub>2</sub>O<sub>5</sub><sup>2-</sup>), and Water As Studied by Oxygen-17 Nuclear Magnetic Resonance Spectroscopy
作者:David A. Horner、Robert E. Connick
DOI:10.1021/ic020692n
日期:2003.3.1
SO(3)(2-) + SO(2) + H(2)O, and SO(3)H(-) + SHO(3-) S(2)O(5)(2-) + H(2)O, where the symbol SHO(3-) refers to both isomeric forms of bisulfite ion, one in which the hydrogen is bonded to the sulfur (denoted HSO(3-)) and another in which the hydrogen is bonded to an oxygen atom (denoted SO(3)H(-)). The SO(3)H(-) isomer exchanges oxygen atoms with water much more rapidly than does the HSO(3-) isomer. The
在离子强度为1.0 m的温度,pH和S(IV)浓度范围内,测量了pH-17为2.5至5的亚硫酸氢钠水溶液中氧17的核磁横向弛豫时间。从这些数据确定了亚硫酸氢根离子与水之间的氧交换速率定律,发现与通过反应SHO(3)(-)+ H(+)SO(2)+ H(2)O发生的氧交换一致,SO(3)H(-)+ SHO(3-)SO(3)(2-)+ SO(2)+ H(2)O和SO(3)H(-)+ SHO(3-) S(2)O(5)(2-)+ H(2)O,其中符号SHO(3-)表示亚硫酸氢根离子的两种同分异构形式,其中氢与硫键合(表示为HSO( 3-))以及其中氢与氧原子键合的另一个(表示为SO(3)H(-))。与HSO(3-)异构体相比,SO(3)H(-)异构体与水交换氧原子的速度要快得多。确定了k(-1)的值,该值与先前通过松弛测量确定的结果基本一致。还发现k(16a)+ k(16b)的值,并且k(16b)至