20.23 The mutarotation of glucose is first order in glucose con- centration and is catalyzed by...

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20.23 The mutarotation of glucose is first order in glucose con- centration and is catalyzed by acids (A) and bases (B). The first- order rate constant may be expressed by an equation of the type that is encountered in reactions with parallel paths: k = ko + kH+ [H*]+ ka[A] + kB[B] %3D where ko is the first-order rate constant in the absence of acids and bases other than water. The following data were obtained by J. N. Brønsted and E. A. Guggenheim [J. Am. Chem. Soc. 49:2554 (1927)] at 18°C in a medium containing 0.02 mol L-1 sodium acetate and various concentrations of acetic acid: [CH3CO,H]/mol L-1 k/10-4 min-1 0.020 0.105 0.199 1.36 1.40 1.46 Calculate ko and kA. The term involving kH+ is negligible under these conditions. 20.23 The mutarotation of glucose is first order in glucose con- centration and is catalyzed by acids (A) and bases (B). The first- order rate constant may be expressed by an equation of the type that is encountered in reactions with parallel paths: k = ko + kH+ [H*]+ ka[A] + kB[B] %3D where ko is the first-order rate constant in the absence of acids and bases other than water. The following data were obtained by J. N. Brønsted and E. A. Guggenheim [J. Am. Chem. Soc. 49:2554 (1927)] at 18°C in a medium containing 0.02 mol L-1 sodium acetate and various concentrations of acetic acid: [CH3CO,H]/mol L-1 k/10-4 min-1 0.020 0.105 0.199 1.36 1.40 1.46 Calculate ko and kA. The term involving kH+ is negligible under these conditions.