Syllabus problem 6.19

[William_Hora_2H]

Could someone explain their reasonings for this two-part question? Thanks in advance.

[Kaitlin Eblen 1I]

This problem (although fancily worded) is about le chatelier's principle. Basically, when the dynamic equilibrium of the given chemical equation is disturbed, the position of equilibrium moves to counteract the change.

A) Lactic acid is an acid, so it produces H3O+ ions when dissociated in water (and blood is mostly water). So if the concentration of hydronium ions (a reactant) increases, the equilibrium shifts to the right (favors the products). This means that HbO2- will decrease.

B) I believe this question is just asking us what would happen if the concen. of oxygen increased. And since O2 is a product, equilibrium would shift to the left (favor reactants). And HbO2- would increase.