Effects of the redistribution of water in the solar nebula on nebular chemistry

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Abstract
We quantify the effects on solar nebula chemistry of variations in the C to O ratio brought on by diffusive and advective redistribution of water vapor. The SOLGASMIX chemical equilibrium code was used to compute abundances of nebular elements and major molecular species, C, N, S and others, for a variety of water‐depleted nebular settings produced by the water distribution models, and for low‐ and high‐pressure (10−5 and 10−3 atm) nebulae. Both relatively oxidizing and reducing nebular conditions can occur across 0.1–5 AU, varying over time. This variety of conditions may help explain the variation in oxidation state of meteorites. Additionally, abundances of organics increase over what would be expected to form from a solar composition gas. Modest increases occur in a relatively oxidizing nebula assuming a solar C/O ratio of 0.42, while large increases of several orders of magnitude occur in a more reducing nebula with solar C/O of 0.6. The increase in organics in the inner nebula could have allowed local accretion of organics to the terrestrial planets, and perhaps supplied organics to the Jovian planetesimal formation region and beyond via outward mixing processes. Lastly, nebular water could have been directly supplied to Earth and the other terrestrial planets via icy body drift and scattering.