Simultaneous Gas Phase Reactions

When more than one chemical reaction achieves equilibrium, a mass action law must be written for each. The analytical tool of choice is the reaction progress variable method.

Example: Dissociation of water vapor.

At low temperatures, water vapor (steam) does not dissociate, and chemical reactions can be neglected. At high temperature (> ~ 1500 K), dissociation into H2 and O2 becomes significant; at very high temperatures, as might occur in the exhaust of a rocket, the hydroxyl radical, OH, appears. The equilibrium reactions governing the concentrations of the four species are:

Assuming the total pressure to be 1 atm, the mass-action expressions for the above equilibria are:

Getting Started With Solar

Getting Started With Solar

Do we really want the one thing that gives us its resources unconditionally to suffer even more than it is suffering now? Nature, is a part of our being from the earliest human days. We respect Nature and it gives us its bounty, but in the recent past greedy money hungry corporations have made us all so destructive, so wasteful.

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