ln(k₁) (crosses) and ln(k₂) (circles) as a function of the inverse of the temperature, k₁ and k₂ being the rates for the HNCO + H₂O  →  OCN⁻+H₃O⁺ and the OCN⁻+H₃O⁺  →  HOCN + H₂O reactions respectively. The uncertainty on a point is given by the dispersion of the measurements for the same temperature around the averaged value. The dashed lines represent the fit of the experimental points against an Arrhenius law.