A student mixes four reagents together, thinking that the solution will neutralize each other. The solutions mixed together are 53.6 mL of 0.129 M hydrochloric acid, 100.6 mL of 0.215 M of nitric acid, 500.9 mL of 0.0100 M calcium hydroxide, and 200.1 mL of 0.122 M rubidium hydroxide.
Calculate the concentration of excess OH- ions left in solution.