TY - JOUR
T1 - The pulse radiolysis of aqueous tetranitromethane. I. Rate constants and the extinction coefficient of eaq-· II. Oxygenated solutions
AU - Rabani, Joseph
AU - Mulac, William A.
AU - Matheson, Max S.
PY - 1965
Y1 - 1965
N2 - Aqueous solutions of tetranitromethane (TNM), both deaerated and oxygenated, have been investigated by the technique of pulsed radiolysis. This system enabled the direct determination of ∈e5780, the extinction coefficient of the hydrated electron, at 5780 Å. as 10,600 (±10%) M-1 cm.-1. ∈e5780 is essential for evaluating rate constants previously determined as k/∈e5780. Also from ∈e5780 we calculate Ge = 2.6 from values of Ge × ∈e5780 in the literature. A number of rate constants were determined, including k(eaq- + TNM) = 4.6 × 1010 M-1 sec.-1, k(H + TNM) = 5.5 × 108 M-1 sec.-1, and k(eaq- + NF-) = 3.0 × 1010 M-1 sec.-1, where NF- is the nitroform ion. Rate constants have also been measured for reaction of several organic radicals with TNM. In the presence of O2, k(O2- + TNM) was measured as 1.9 × 109 M-1 sec.-1. k(HO2 + TNM) is less than 10-5 as large. Measurement of the effective k as a function of pH gave pK = 4.45 ± 0.25 for the dissociation, HO2 ⇌ H+ + O2-.
AB - Aqueous solutions of tetranitromethane (TNM), both deaerated and oxygenated, have been investigated by the technique of pulsed radiolysis. This system enabled the direct determination of ∈e5780, the extinction coefficient of the hydrated electron, at 5780 Å. as 10,600 (±10%) M-1 cm.-1. ∈e5780 is essential for evaluating rate constants previously determined as k/∈e5780. Also from ∈e5780 we calculate Ge = 2.6 from values of Ge × ∈e5780 in the literature. A number of rate constants were determined, including k(eaq- + TNM) = 4.6 × 1010 M-1 sec.-1, k(H + TNM) = 5.5 × 108 M-1 sec.-1, and k(eaq- + NF-) = 3.0 × 1010 M-1 sec.-1, where NF- is the nitroform ion. Rate constants have also been measured for reaction of several organic radicals with TNM. In the presence of O2, k(O2- + TNM) was measured as 1.9 × 109 M-1 sec.-1. k(HO2 + TNM) is less than 10-5 as large. Measurement of the effective k as a function of pH gave pK = 4.45 ± 0.25 for the dissociation, HO2 ⇌ H+ + O2-.
UR - http://www.scopus.com/inward/record.url?scp=0003055931&partnerID=8YFLogxK
U2 - 10.1021/j100885a011
DO - 10.1021/j100885a011
M3 - ???researchoutput.researchoutputtypes.contributiontojournal.article???
AN - SCOPUS:0003055931
SN - 0022-3654
VL - 69
SP - 53
EP - 70
JO - Journal of Physical Chemistry
JF - Journal of Physical Chemistry
IS - 1
ER -