Such a contest can lead to stable, and often complex, arrangements of the chemicals' relative concentrations.

比赛结果是化学物质相对浓度形成稳定、通常很复杂的状态。

The overall direction of the reaction is determined by - and this is important - the relative concentration of oxygen.

反应的总方向由氧的相对浓度决定，这一点很重要。