Absolute Rate Constant for the Reaction H+H2CO

The photolysis of formaldehyde in the pronounced absorption region ∼1700–1760 Å has been investigated. The production of H atoms has been established by direct observation using pulsed photolysis and time dependent observation of the Lyman‐α resonance fluorescence at 1216 Å. From the measurement of the H‐atom decay under pseudo‐first order conditions the rate constant for the reaction $$\mathrm{H}+{\mathrm{H}}_2\mathrm{CO}\to {\mathrm{H}}_2+\mathrm{HCO}$$ has been obtained. The result is ${\text{5.4± 0.5× 10}}^{\text{−14}}\hspace{0.17em}{\mathrm{cm}}^3\hspace{0.17em}{\mathrm{molecule}}^{\text{−1}}·{\sec }^{\text{−1}}$ at 297°K.