# How does pH level change the concentration of dissolved oxygen (DO) in sea water?

I am planning to investigate the relationship between $\mathrm{pH}$ and dissolved oxygen.

I would like to have a reason without taking in account the plants, animals and decomposer roles.

I want to know if $\mathrm{pH}$ affects the concentration of dissolved oxygen. For example:

If I added $\ce{HCl}$ to water, would the concentration of DO change? In same way, if I add $\ce{NaOH}$, would the concentration of DO change?

• In short: no, it does not, at least until you reach the truly extreme concentrations. – Ivan Neretin Apr 25 '16 at 5:48

The equilibrium of dissolved-to-gas-phase oxygen is not affected by the aqueous hydronium ion concentration ($\ce{H3O+}$), and thus the pH of water does not affect dissolved oxygen concetrations of sea water.